1
|
Tsoukalas D, Hamed I, Hoel S, Lerfall J, Jakobsen AN. Effect of harvesting season and location on the microbial quality and community composition of the edible sea urchin (Echinus esculentus) gonads. Food Microbiol 2024; 123:104594. [PMID: 39038897 DOI: 10.1016/j.fm.2024.104594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2024] [Revised: 06/07/2024] [Accepted: 07/01/2024] [Indexed: 07/24/2024]
Abstract
Despite the crucial role of microbial community composition in the quality and stability of seafood, little emphasis has been given to the microbiota profile of sea urchin gonads. This study investigates the microbial quality and community composition of sea urchin gonads (Echinus esculentus) as a function of harvesting season (autumn, winter, spring, and summer) and location (one site proximal to urban activity areas while the other is located in open water close to the coastline). Significant season-dependent variations were found in psychrotrophic and aerobic plate counts, with higher counts in summer, followed by autumn, spring, and winter. H2S-producing bacteria and Pseudomonas spp. counts were unaffected by harvesting season or location. Sea urchin gonad microbial composition proved resilient and dynamic, primarily shaped by seasonal variations, and minimally influenced by location. Winter and spring samples exhibited higher diversity than autumn and summer. Key genera like Pseudomonas, Psychromonas, Vibrio, Chryseobacterium, Shewanella, and Photobacterium varied seasonally. Pseudomonas, Vibrio, and Photobacterium are crucial in assessing microbial quality and safety due to their roles as specific spoilage organisms (SSOs) and, in some cases, human pathogens. Though relative abundances differed slightly between locations, harvesting location did not notably impact microbial community shaping in gonads. However, the results suggest that harvesting locations near areas with urban activity may lead to contamination with specific bacterial species, possibly due to water quality variations. These findings emphasize the importance of considering seasonality when evaluating sea urchin gonad microbial quality. Identifying key genera enhances insights into potential SSOs and human pathogens, enhancing food safety considerations in the consumption of raw or lightly processed sea urchin gonads and guiding the development of preservation methods to extend shelf life.
Collapse
Affiliation(s)
- Dionysios Tsoukalas
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), NO-7491, Trondheim, Norway.
| | - Imen Hamed
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), NO-7491, Trondheim, Norway
| | - Sunniva Hoel
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), NO-7491, Trondheim, Norway
| | - Jørgen Lerfall
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), NO-7491, Trondheim, Norway
| | - Anita Nordeng Jakobsen
- Department of Biotechnology and Food Science, Norwegian University of Science and Technology (NTNU), NO-7491, Trondheim, Norway
| |
Collapse
|
2
|
Smith NM, Boissonneault KR, Holden PN, Kaur JN, Klem JF, Cha R, Sutton MD, Tsuji BT. PBP-3 directed therapy in VIM-producing Pseudomonas aeruginosa creates bacterial transformers, persisters in disguise. Int J Antimicrob Agents 2024; 64:107260. [PMID: 38945177 DOI: 10.1016/j.ijantimicag.2024.107260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 05/03/2024] [Accepted: 06/16/2024] [Indexed: 07/02/2024]
Abstract
OBJECTIVES The proliferation of metallo-β-lactamase (MBL)-producing Pseudomonas aeruginosa represents a significant public health threat. P. aeruginosa undergoes significant phenotypic changes that drastically impair antibiotic efficacy. The objectives of this study were (1) to quantify the time-course of killing of VIM-2-producing P. aeruginosa in response to aztreonam-based therapies (including avibactam for coverage of AmpC), and (2) to document the capacity of P. aeruginosa to undergo morphological transformations that facilitate persistence. METHODS A well-characterised, clinical VIM-2-producing P. aeruginosa was studied in the hollow fibre infection model (HFIM) over 9 days (7 days of active antibiotic therapy, 2 days of treatment withdrawal) at a 107.5 CFU/mL starting inoculum. HFIM treatment arms included: growth control, aztreonam, ceftazidime/avibactam, aztreonam/ceftazidime/avibactam, polymyxin B, and aztreonam/ceftazidime/avibactam/polymyxin B. In addition, real-time imaging studies were conducted under static conditions to determine the time course of the reversion of persister cells. RESULTS There was a pronounced discrepancy between OD620 and bacterial counts obtained from plating methods (hereafter referred to as 'OD-count discrepancy'). For aztreonam monotherapy, observed counts were 0 CFU/mL by 120 h. Despite this, there was a significant OD-count discrepancy compared with the pre-treatment 0 h. Between therapy withdrawal at 168 h and 216 h, all arms with suppressed counts had regrown to the system-carrying capacity. Real-time imaging of the P. aeruginosa filaments after drug removal showed rapid reversion from a long, filamentous phenotype to many individual rods within 2 h. CONCLUSION Managing MBL-producing P. aeruginosa requires a multifaceted approach, focused on maximising killing and minimising proliferation of resistant and persistent subpopulations, which will involve eliminating drug-induced phenotypic transformers.
Collapse
Affiliation(s)
- Nicholas M Smith
- Division of Clinical and Translational Therapeutics, Department of Pharmacy Practice, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York, USA.
| | - Katie Rose Boissonneault
- Division of Clinical and Translational Therapeutics, Department of Pharmacy Practice, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Patricia N Holden
- Division of Clinical and Translational Therapeutics, Department of Pharmacy Practice, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Jan Naseer Kaur
- Division of Clinical and Translational Therapeutics, Department of Pharmacy Practice, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Jack F Klem
- Division of Clinical and Translational Therapeutics, Department of Pharmacy Practice, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Raymond Cha
- Division of Clinical and Translational Therapeutics, Department of Pharmacy Practice, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Mark D Sutton
- Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, Buffalo, New York, USA
| | - Brian T Tsuji
- Division of Clinical and Translational Therapeutics, Department of Pharmacy Practice, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, New York, USA.
| |
Collapse
|
3
|
Masucci EM, Hauschild JE, Gisler HM, Lester EM, Balss KM. Raman spectroscopy as an alternative rapid microbial bioburden test method for continuous, automated detection of contamination in biopharmaceutical drug substance manufacturing. J Appl Microbiol 2024; 135:lxae188. [PMID: 39054049 DOI: 10.1093/jambio/lxae188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 07/10/2024] [Accepted: 07/23/2024] [Indexed: 07/27/2024]
Abstract
AIMS To investigate an in-line Raman method capable of detecting accidental microbial contamination in pharmaceutical vessels, such as bioreactors producing monoclonal antibodies via cell culture. METHODS AND RESULTS The Raman method consists of a multivariate model built from Raman spectra collected in-line during reduced-scale bioreactor batches producing a monoclonal antibody, as well as a reduced-scale process with intentional spiking of representative compendial method microorganisms (n = 4). The orthogonal partial least squares regression discriminant analysis model (OPLS-DA) area under the curve (AUC), specificity and sensitivity were 0.96, 0.99, and 0.95, respectively. Furthermore, the model successfully detected contamination in an accidentally contaminated manufacturing-scale batch. In all cases, the time to detection (TTD) for Raman was superior compared to offline, traditional microbiological culturing. CONCLUSIONS The Raman OPLS-DA method met acceptance criteria for equivalent decision making to be considered a viable alternative to the compendial method for in-process bioburden testing. The in-line method is automated, non-destructive, and provides a continuous assessment of bioburden compared to an offline compendial method, which is manual, results in loss of product, and in practice is only collected once daily and requires 3-5 days for enumeration.
Collapse
Affiliation(s)
- Erin M Masucci
- Emerging Technologies, Manufacturing Science and Technology Janssen Pharmaceuticals Inc., Welsh and McKean Roads, Spring House, PA 19477, USA
| | - James E Hauschild
- Microbiological Quality and Sterility Assurance Johnson & Johnson Services, Inc., Raritan, NJ 08869, USA
| | - Helena M Gisler
- Emerging Technologies, Manufacturing Science and Technology Janssen Pharmaceuticals Inc., Welsh and McKean Roads, Spring House, PA 19477, USA
| | - Erin M Lester
- Emerging Technologies, Manufacturing Science and Technology Janssen Pharmaceuticals Inc., Welsh and McKean Roads, Spring House, PA 19477, USA
| | - Karin M Balss
- Emerging Technologies, Manufacturing Science and Technology Janssen Pharmaceuticals Inc., Welsh and McKean Roads, Spring House, PA 19477, USA
| |
Collapse
|
4
|
Poteete O, Cox P, Ruffin F, Sutton G, Brinkac L, Clarke TH, Fouts DE, Fowler VG, Thaden JT. Serum susceptibility of Escherichia coli and its association with patient clinical outcomes. PLoS One 2024; 19:e0307968. [PMID: 39074102 DOI: 10.1371/journal.pone.0307968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 07/14/2024] [Indexed: 07/31/2024] Open
Abstract
The innate immune system eliminates bloodstream pathogens such as Escherichia coli in part through complement protein deposition and subsequent bacterial death (i.e., "serum killing"). Some E. coli strains have developed mechanisms to resist serum killing, though the extent of variation in serum killing among bloodstream infection (BSI) isolates and the clinical impact of this variation is not well understood. To address this issue, we developed a novel assay that uses flow cytometry to perform high throughput serum bactericidal assays (SBAs) with E. coli BSI isolates (n = 183) to define the proportion of surviving bacteria after exposure to serum. We further determined whether E. coli resistance to serum killing is associated with clinical outcomes (e.g., in-hospital attributable mortality, in-hospital total mortality, septic shock) and bacterial genotype in the corresponding patients with E. coli BSI. Our novel flow cytometry-based SBA performed similarly to a traditional SBA, though with significantly decreased hands-on bench work. Among E. coli BSI isolates, the mean proportion that survived exposure to 25% serum was 0.68 (Standard deviation 0.02, range 0.57-0.93). We did not identify associations between E. coli resistance to serum killing and clinical outcomes in our adjusted models. Together, this study describes a novel flow cytometry-based approach to the bacterial SBA that allowed for high-throughput testing of E. coli BSI isolates and identified high variability in resistance to serum killing among a large set of BSI isolates.
Collapse
Affiliation(s)
- Orianna Poteete
- Department of Medicine, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, United States of America
| | - Phillip Cox
- Department of Medicine, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, United States of America
| | - Felicia Ruffin
- Department of Medicine, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, United States of America
| | - Granger Sutton
- J. Craig Venter Institute, Rockville, MD, United States of America
| | - Lauren Brinkac
- J. Craig Venter Institute, Rockville, MD, United States of America
| | - Thomas H Clarke
- J. Craig Venter Institute, Rockville, MD, United States of America
| | - Derrick E Fouts
- J. Craig Venter Institute, Rockville, MD, United States of America
| | - Vance G Fowler
- Department of Medicine, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, United States of America
- Duke Clinical Research Institute, Durham, NC, United States of America
| | - Joshua T Thaden
- Department of Medicine, Division of Infectious Diseases, Duke University School of Medicine, Durham, NC, United States of America
| |
Collapse
|
5
|
He S, Chen Y, Wang J, Sun J, Zhang X, Chen Q. Rapid and Sensitive Quantification of Bacterial Viability Using Ratiometric Fluorescence Sensing. Anal Chem 2024; 96:11018-11025. [PMID: 38934709 DOI: 10.1021/acs.analchem.4c01737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2024]
Abstract
Bacterial viability assessment plays an important role in food-borne pathogen detection and antimicrobial drug development. Here, we first used GelRed as a DNA-binding stain for a bacterial viability assessment. It was found that live bacteria were able to exclude GelRed, which however could easily penetrate dead ones and be absorbed nonspecifically on the bacterial periplasm. Cations were used to reduce the nonspecific adsorption and greatly increase the red fluorescence ratio of dead to live bacteria. Combined with SYTO 9 (a membrane-permeable dye) for double-staining, a ratiometric fluorescent method was established. Using Escherichia coli O157:H7 as a bacteria model, the ratiometric fluorescent method can probe dead bacteria as low as 0.1%. A linear correlation between the ratiometric fluorescence and the theoretical ratio of dead bacteria was acquired, with a correlation coefficient R2 of 0.97. Advantages in sensitivity, accuracy, and safety of the GelRed/SYTO9-based ratiometric fluorescent method against traditional methods were demonstrated. The established method was successfully applied to the assessment of germicidal efficacy of different heat treatments. It was found that even 50 °C treatment could lead to the death of minor bacteria. The as-developed method has many potential applications in microbial researches, and we believe it could be expanded to the viability assessment of mammalian cells.
Collapse
Affiliation(s)
- Shengbin He
- Key Laboratory of Longevity and Aging-related Diseases of Chinese Ministry of Education, Guangxi Colleges and Universities Key Laboratory of Biological Molecular Medicine Research, School of Basic Medical Sciences, Guangxi Medical University, Nanning, Guangxi 530021, P. R. China
| | - Yajing Chen
- Key Laboratory of Longevity and Aging-related Diseases of Chinese Ministry of Education, Guangxi Colleges and Universities Key Laboratory of Biological Molecular Medicine Research, School of Basic Medical Sciences, Guangxi Medical University, Nanning, Guangxi 530021, P. R. China
| | - Jingtong Wang
- Key Laboratory of Longevity and Aging-related Diseases of Chinese Ministry of Education, Guangxi Colleges and Universities Key Laboratory of Biological Molecular Medicine Research, School of Basic Medical Sciences, Guangxi Medical University, Nanning, Guangxi 530021, P. R. China
| | - Jian Sun
- Key Laboratory of Longevity and Aging-related Diseases of Chinese Ministry of Education, Guangxi Colleges and Universities Key Laboratory of Biological Molecular Medicine Research, School of Basic Medical Sciences, Guangxi Medical University, Nanning, Guangxi 530021, P. R. China
| | - Xinyi Zhang
- Key Laboratory of Longevity and Aging-related Diseases of Chinese Ministry of Education, Guangxi Colleges and Universities Key Laboratory of Biological Molecular Medicine Research, School of Basic Medical Sciences, Guangxi Medical University, Nanning, Guangxi 530021, P. R. China
| | - Quanzhi Chen
- Key Laboratory of Longevity and Aging-related Diseases of Chinese Ministry of Education, Guangxi Colleges and Universities Key Laboratory of Biological Molecular Medicine Research, School of Basic Medical Sciences, Guangxi Medical University, Nanning, Guangxi 530021, P. R. China
| |
Collapse
|
6
|
Bourdin T, Benoit MÈ, Prévost M, Charron D, Quach C, Déziel E, Constant P, Bédard E. Disinfection of sink drains to reduce a source of three opportunistic pathogens, during Serratia marcescens clusters in a neonatal intensive care unit. PLoS One 2024; 19:e0304378. [PMID: 38865328 PMCID: PMC11168660 DOI: 10.1371/journal.pone.0304378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 05/10/2024] [Indexed: 06/14/2024] Open
Abstract
OBJECTIVE Evaluate the effects of five disinfection methods on bacterial concentrations in hospital sink drains, focusing on three opportunistic pathogens (OPs): Serratia marcescens, Pseudomonas aeruginosa and Stenotrophomonas maltophilia. DESIGN Over two years, three sampling campaigns were conducted in a neonatal intensive care unit (NICU). Samples from 19 sink drains were taken at three time points: before, during, and after disinfection. Bacterial concentration was measured using culture-based and flow cytometry methods. High-throughput short sequence typing was performed to identify the three OPs and assess S. marcescens persistence after disinfection at the genotypic level. SETTING This study was conducted in a pediatric hospitals NICU in Montréal, Canada, which is divided in an intensive and intermediate care side, with individual rooms equipped with a sink. INTERVENTIONS Five treatments were compared: self-disinfecting drains, chlorine disinfection, boiling water disinfection, hot tap water flushing, and steam disinfection. RESULTS This study highlights significant differences in the effectiveness of disinfection methods. Chlorine treatment proved ineffective in reducing bacterial concentration, including the three OPs. In contrast, all other drain interventions resulted in an immediate reduction in culturable bacteria (4-8 log) and intact cells (2-3 log). Thermal methods, particularly boiling water and steam treatments, exhibited superior effectiveness in reducing bacterial loads, including OPs. However, in drains with well-established bacterial biofilms, clonal strains of S. marcescens recolonized the drains after heat treatments. CONCLUSIONS Our study supports thermal disinfection (>80°C) for pathogen reduction in drains but highlights the need for additional trials and the implementation of specific measures to limit biofilm formation.
Collapse
Affiliation(s)
| | | | | | | | - Caroline Quach
- CHU Sainte-Justine, Université de Montréal, Montréal, QC, Canada
| | - Eric Déziel
- INRS-Armand-Frappier Santé Biotechnologie, Laval, QC, Canada
| | | | | |
Collapse
|
7
|
Teixeira CG, Belguesmia Y, da Silva Rodrigues R, Lucau-Danila A, Nero LA, de Carvalho AF, Drider D. Assessment of safety and in situ antibacterial activity of Weissella cibaria strains isolated from dairy farms in Minas Gerais State, Brazil, for their food application. Braz J Microbiol 2024; 55:699-710. [PMID: 38253975 PMCID: PMC10920571 DOI: 10.1007/s42770-023-01244-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 12/29/2023] [Indexed: 01/24/2024] Open
Abstract
Weissella cibaria W21, W25, and W42 strains have previously been characterized for their antagonism against a range of foodborne pathogens. However, prior to their use as protective agents, further analyses such as their safety and in situ activity are needed. The safety of W. cibaria W21, W25, and W42 strains was predicted in silico and confirmed experimentally. Analyses of their genomes using appropriate software did not reveal any acquired antimicrobial resistance genes, nor mobile genetic elements (MGEs). The survival of each strain was determined in vitro under conditions mimicking the gastrointestinal tract (GIT). Thus, hemolysis analysis was performed using blood agar and the cytotoxicity assay was determined using a mixture of two cell lines (80% of Caco-2 and 20% of HT-29). We also performed the inflammation and anti-inflammation capabilities of these strains using the promonocytic human cell line U937. The Weissella strains were found to be haemolysis-negative and non-cytotoxic and did not induce any inflammation. Furthermore, these strains adhered tightly to intestinal Caco-2 cell-lines and exerted in situ anti-proliferative activity against methicillin-resistant Staphylococcus aureus (strain MRSA S1) and Escherichia coli 181, a colistin-resistant strain. However, the W. cibaria strains showed low survival rate under simulated GIT conditions in vitro. The unusual LAB-strains W. cibaria strains W21, W25, and W42 are safe and endowed with potent antibacterial activities. These strains are therefore good candidates for industrial applications. The results of this study provide a characterization and insights into Weissella strains, which are considered unusual LAB, but which prompt a growing interest in their bio-functional properties and their potential industrial applications.
Collapse
Affiliation(s)
- Camila Gonçalves Teixeira
- InovaLeite-Laboratório de Pesquisa em Leite e Derivados, Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa, Viçosa, MG, 36570 900, Brazil
- Unité Mixte de Recherche (UMR) Transfrontalière BioEcoAgro1158, Univ. Lille, INRAE, Univ. Liège, UPJV, YNCREA, Univ. Artois, Univ. Littoral Côte D'Opale, ICV-Institut Charles Viollette, 59000, Lille, France
| | - Yanath Belguesmia
- Unité Mixte de Recherche (UMR) Transfrontalière BioEcoAgro1158, Univ. Lille, INRAE, Univ. Liège, UPJV, YNCREA, Univ. Artois, Univ. Littoral Côte D'Opale, ICV-Institut Charles Viollette, 59000, Lille, France
| | - Rafaela da Silva Rodrigues
- InovaLeite-Laboratório de Pesquisa em Leite e Derivados, Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa, Viçosa, MG, 36570 900, Brazil
- InsPOA-Laboratório de Inspeção de Produtos de Origem Animal, Departamento de Veterinária, Universidade Federal de Viçosa, Viçosa, MG, 36570 900, Brazil
| | - Anca Lucau-Danila
- Unité Mixte de Recherche (UMR) Transfrontalière BioEcoAgro1158, Univ. Lille, INRAE, Univ. Liège, UPJV, YNCREA, Univ. Artois, Univ. Littoral Côte D'Opale, ICV-Institut Charles Viollette, 59000, Lille, France
| | - Luís Augusto Nero
- InsPOA-Laboratório de Inspeção de Produtos de Origem Animal, Departamento de Veterinária, Universidade Federal de Viçosa, Viçosa, MG, 36570 900, Brazil
| | - Antônio Fernandes de Carvalho
- InovaLeite-Laboratório de Pesquisa em Leite e Derivados, Departamento de Tecnologia de Alimentos, Universidade Federal de Viçosa, Viçosa, MG, 36570 900, Brazil.
| | - Djamel Drider
- Unité Mixte de Recherche (UMR) Transfrontalière BioEcoAgro1158, Univ. Lille, INRAE, Univ. Liège, UPJV, YNCREA, Univ. Artois, Univ. Littoral Côte D'Opale, ICV-Institut Charles Viollette, 59000, Lille, France.
| |
Collapse
|
8
|
Zhuang L, Gong J, Zhao Y, Yang J, Liu G, Zhao B, Song C, Zhang Y, Shen Q. Progress in methods for the detection of viable Escherichia coli. Analyst 2024; 149:1022-1049. [PMID: 38273740 DOI: 10.1039/d3an01750h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2024]
Abstract
Escherichia coli (E. coli) is a prevalent enteric bacterium and a necessary organism to monitor for food safety and environmental purposes. Developing efficient and specific methods is critical for detecting and monitoring viable E. coli due to its high prevalence. Conventional culture methods are often laborious and time-consuming, and they offer limited capability in detecting potentially harmful viable but non-culturable E. coli in the tested sample, which highlights the need for improved approaches. Hence, there is a growing demand for accurate and sensitive methods to determine the presence of viable E. coli. This paper scrutinizes various methods for detecting viable E. coli, including culture-based methods, molecular methods that target DNAs and RNAs, bacteriophage-based methods, biosensors, and other emerging technologies. The review serves as a guide for researchers seeking additional methodological options and aiding in the development of rapid and precise assays. Moving forward, it is anticipated that methods for detecting E. coli will become more stable and robust, ultimately contributing significantly to the improvement of food safety and public health.
Collapse
Affiliation(s)
- Linlin Zhuang
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong 212400, P. R. China.
- State Key Laboratory of Digital Medical Engineering, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering & Basic Medicine Research and Innovation Center of Ministry of Education, Zhongda Hospital, Southeast University, Nanjing 211102, P. R. China.
| | - Jiansen Gong
- Poultry Institute, Chinese Academy of Agricultural Sciences, Yangzhou 225125, P. R. China
| | - Ying Zhao
- State Key Laboratory of Digital Medical Engineering, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering & Basic Medicine Research and Innovation Center of Ministry of Education, Zhongda Hospital, Southeast University, Nanjing 211102, P. R. China.
| | - Jianbo Yang
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong 212400, P. R. China.
| | - Guofang Liu
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong 212400, P. R. China.
| | - Bin Zhao
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong 212400, P. R. China.
| | - Chunlei Song
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong 212400, P. R. China.
| | - Yu Zhang
- State Key Laboratory of Digital Medical Engineering, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering & Basic Medicine Research and Innovation Center of Ministry of Education, Zhongda Hospital, Southeast University, Nanjing 211102, P. R. China.
| | - Qiuping Shen
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong 212400, P. R. China.
| |
Collapse
|
9
|
Zhuang L, Gong J, Shen Q, Yang J, Song C, Liu Q, Zhao B, Zhang Y, Zhu M. Advances in detection methods for viable Salmonella spp.: current applications and challenges. ANAL SCI 2023; 39:1643-1660. [PMID: 37378821 DOI: 10.1007/s44211-023-00384-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2023] [Accepted: 06/08/2023] [Indexed: 06/29/2023]
Abstract
Salmonella is a common intestinal pathogen that can cause food poisoning and intestinal disease. The high prevalence of Salmonella necessitates efficient and sensitive methods for its identification, detection, and monitoring, especially of viable Salmonella. Conventional culture methods need to be more laborious and time-consuming. And they are relatively limited in their ability to detect Salmonella in the viable but non-culturable status if present in the sample to be tested. As a result, there is an increasing need for rapid and accurate techniques to detect viable Salmonella spp. This paper reviewed the status and progress of various methods reported in recent years that can be used to detect viable Salmonella, such as culture-based methods, molecular methods targeting RNAs and DNAs, phage-based methods, biosensors, and some techniques that have the potential for future application. This review can provide researchers with a reference for additional method options and help facilitate the development of rapid and accurate assays. In the future, viable Salmonella detection approaches will become more stable, sensitive, and fast and are expected to play a more significant role in food safety and public health.
Collapse
Affiliation(s)
- Linlin Zhuang
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong, 212400, People's Republic of China
- State Key Laboratory of Digital Medical Engineering, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering and Collaborative Innovation Center of Suzhou Nano Science and Technology, Southeast University, Nanjing, 210096, People's Republic of China
| | - Jiansen Gong
- Poultry Institute, Chinese Academy of Agricultural Sciences, Yangzhou, 225125, People's Republic of China
| | - Qiuping Shen
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong, 212400, People's Republic of China
| | - Jianbo Yang
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong, 212400, People's Republic of China
| | - Chunlei Song
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong, 212400, People's Republic of China
| | - Qingxin Liu
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong, 212400, People's Republic of China
| | - Bin Zhao
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong, 212400, People's Republic of China
| | - Yu Zhang
- State Key Laboratory of Digital Medical Engineering, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering and Collaborative Innovation Center of Suzhou Nano Science and Technology, Southeast University, Nanjing, 210096, People's Republic of China.
| | - Mengling Zhu
- School of Animal Husbandry and Veterinary Medicine, Jiangsu Vocational College of Agriculture and Forestry, Jurong, 212400, People's Republic of China.
| |
Collapse
|
10
|
Komori E, Kato-Kogoe N, Imai Y, Sakaguchi S, Taniguchi K, Omori M, Ohmichi M, Nakamura S, Nakano T, Lee SW, Ueno T. Changes in salivary microbiota due to gastric cancer resection and its relation to gastric fluid microbiota. Sci Rep 2023; 13:15863. [PMID: 37740058 PMCID: PMC10516953 DOI: 10.1038/s41598-023-43108-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 09/20/2023] [Indexed: 09/24/2023] Open
Abstract
Gastric cancer is one of the leading causes of death worldwide, and resections are performed to cure the disease. We have previously reported the changes in the gastric microbiota after gastric cancer resection, which may be associated with the oral microbiota; however, the changes in the oral microbiota remain uncharacterized. This study aimed to characterize the changes in the salivary microbiota caused by gastric cancer resection and to evaluate their association with the gastric fluid microbiota. Saliva and gastric fluid samples were collected from 63 patients who underwent gastrectomy before and after surgery, and a 16S rRNA metagenomic analysis was performed to compare the microbiota composition. The number of bacterial species in the salivary microbiota decreased, and the bacterial composition changed after the resection of gastric cancer. In addition, we identified several bacterial genera that varied significantly in the salivary microbiota, some of which also showed similar changes in the gastric fluid microbiota. These findings indicate that changes in the gastric environment affect the oral microbiota, emphasizing the close association between the oral and gastric fluid microbiota. Our study signifies the importance of focusing on the oral microbiota in the perioperative period of gastrectomy in patients with gastric cancer.
Collapse
Affiliation(s)
- Eri Komori
- Department of Dentistry and Oral Surgery, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki City, Osaka, 569-8686, Japan
| | - Nahoko Kato-Kogoe
- Department of Dentistry and Oral Surgery, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki City, Osaka, 569-8686, Japan.
| | - Yoshiro Imai
- Department of General and Gastroenterological Surgery, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki City, Osaka, 569-8686, Japan
| | - Shoichi Sakaguchi
- Department of Microbiology and Infection Control, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki City, Osaka, 569-8686, Japan
| | - Kohei Taniguchi
- Translational Research Program, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki City, Osaka, 569-8686, Japan
| | - Michi Omori
- Department of Dentistry and Oral Surgery, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki City, Osaka, 569-8686, Japan
| | - Mayu Ohmichi
- Department of Dentistry and Oral Surgery, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki City, Osaka, 569-8686, Japan
| | - Shota Nakamura
- Department of Infection Metagenomics, Genome Information Research Center, Research Institute for Microbial Diseases, Osaka University, Suita, Japan
| | - Takashi Nakano
- Department of Microbiology and Infection Control, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki City, Osaka, 569-8686, Japan
| | - Sang-Woong Lee
- Department of General and Gastroenterological Surgery, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki City, Osaka, 569-8686, Japan
| | - Takaaki Ueno
- Department of Dentistry and Oral Surgery, Faculty of Medicine, Osaka Medical and Pharmaceutical University, 2-7 Daigaku-machi, Takatsuki City, Osaka, 569-8686, Japan
| |
Collapse
|
11
|
Marcos-Fernández R, Sánchez B, Ruiz L, Margolles A. Convergence of flow cytometry and bacteriology. Current and future applications: a focus on food and clinical microbiology. Crit Rev Microbiol 2023; 49:556-577. [PMID: 35749433 DOI: 10.1080/1040841x.2022.2086035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 05/12/2022] [Accepted: 05/31/2022] [Indexed: 11/03/2022]
Abstract
Since its development in the 1960s, flow cytometry (FCM) was quickly revealed a powerful tool to analyse cell populations in medical studies, yet, for many years, was almost exclusively used to analyse eukaryotic cells. Instrument and methodological limitations to distinguish genuine bacterial signals from the background, among other limitations, have hampered FCM applications in bacteriology. In recent years, thanks to the continuous development of FCM instruments and methods with a higher discriminatory capacity to detect low-size particles, FCM has emerged as an appealing technique to advance the study of microbes, with important applications in research, clinical and industrial settings. The capacity to rapidly enumerate and classify individual bacterial cells based on viability facilitates the monitoring of bacterial presence in foodstuffs or clinical samples, reducing the time needed to detect contamination or infectious processes. Besides, FCM has stood out as a valuable tool to advance the study of complex microbial communities, or microbiomes, that are very relevant in the context of human health, as well as to understand the interaction of bacterial and host cells. This review highlights current developments in, and future applications of, FCM in bacteriology, with a focus on those related to food and clinical microbiology.
Collapse
Affiliation(s)
- Raquel Marcos-Fernández
- Department of Microbiology and Biochemistry of Dairy Products, Dairy Research Institute of Asturias, Spanish National Research Council (IPLA-CSIC), Asturias, Spain
- Functionality and Ecology of Beneficial Microbes (MicroHealth) Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Asturias, Spain
| | - Borja Sánchez
- Department of Microbiology and Biochemistry of Dairy Products, Dairy Research Institute of Asturias, Spanish National Research Council (IPLA-CSIC), Asturias, Spain
- Functionality and Ecology of Beneficial Microbes (MicroHealth) Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Asturias, Spain
| | - Lorena Ruiz
- Department of Microbiology and Biochemistry of Dairy Products, Dairy Research Institute of Asturias, Spanish National Research Council (IPLA-CSIC), Asturias, Spain
- Functionality and Ecology of Beneficial Microbes (MicroHealth) Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Asturias, Spain
| | - Abelardo Margolles
- Department of Microbiology and Biochemistry of Dairy Products, Dairy Research Institute of Asturias, Spanish National Research Council (IPLA-CSIC), Asturias, Spain
- Functionality and Ecology of Beneficial Microbes (MicroHealth) Group, Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Asturias, Spain
| |
Collapse
|
12
|
Ding N, Li Z, Jiang L, Liu H, Zhang Y, Sun Y. Kinetics and mechanisms of bacteria disinfection by performic acid in wastewater: In comparison with peracetic acid and sodium hypochlorite. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 878:162606. [PMID: 36906014 DOI: 10.1016/j.scitotenv.2023.162606] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 02/27/2023] [Accepted: 02/28/2023] [Indexed: 05/13/2023]
Abstract
Performic acid (PFA) has been increasingly used in wastewater disinfection due to its strong oxidizing ability and few disinfection byproducts. However, its disinfection pathways and mechanisms towards pathogenic bacteria disinfection are poorly understood. In this study, E. coli, S. aureus, and B. subtilis were inactivated using sodium hypochlorite (NaClO), PFA, and peracetic acid (PAA) in simulated turbid water and municipal secondary effluent. Cell culture-based plate counting showed that E. coli and S. aureus were extremely susceptible to NaClO and PFA and achieved a 4-log inactivation at CTs ≤ 1 mg/L·min with an initial disinfectant concentration of 0.3 mg/L. B. subtilis was much more resistant. At the initial disinfectant dose of 7.5 mg/L, PFA required CTs of 3-13 mg/L·min to achieve a 4-log inactivation. Turbidity negatively affected the disinfection. In the secondary effluent, the CTs required for PFA to achieve a 4-log inactivation of E. coli and B. subtilis were 6-12 times higher than those required in simulated turbid water, and a 4-log inactivation of S. aureus could not be achieved. PAA showed a much weaker disinfection ability than the other two disinfectants. The reaction pathways of E. coli inactivation by PFA included both direct and indirect reactions, in which the PFA molecule accounted for 73 %, and ·OH and peroxide radicals accounted for 20 % and 6 %, respectively. During PFA disinfection, E. coli cells were severely disintegrated, while the S. aureus cell exteriors remained mostly intact. B. subtilis was the least affected. Compared with cell culture-based analysis, the inactivation detected by flow cytometry was significantly lower. Viable but non-culturable bacteria after disinfection were believed to be primarily responsible for this inconsistency. This study suggested that PFA was able to control regular bacteria in wastewater, but it should be used with caution when treating recalcitrant pathogens.
Collapse
Affiliation(s)
- Ning Ding
- School of Ecology and Environment, Beijing Technology and Business University, Beijing, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing, China; Key Laboratory of Cleaner Production and Comprehensive Utilization of Resources, China National Light Industry, Beijing Technology and Business University, Beijing, China
| | - Ziwei Li
- School of Ecology and Environment, Beijing Technology and Business University, Beijing, China
| | - Lin Jiang
- School of Ecology and Environment, Beijing Technology and Business University, Beijing, China
| | - Hong Liu
- School of Environmental Science and Engineering, Suzhou University of Science and Technology, Jiangsu Province, China
| | - Yanping Zhang
- School of Ecology and Environment, Beijing Technology and Business University, Beijing, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing, China; Key Laboratory of Cleaner Production and Comprehensive Utilization of Resources, China National Light Industry, Beijing Technology and Business University, Beijing, China
| | - Yingxue Sun
- School of Ecology and Environment, Beijing Technology and Business University, Beijing, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing, China; Key Laboratory of Cleaner Production and Comprehensive Utilization of Resources, China National Light Industry, Beijing Technology and Business University, Beijing, China.
| |
Collapse
|
13
|
Yang P, Zhao L, Gao YG, Xia Y. Detection, Diagnosis, and Preventive Management of the Bacterial Plant Pathogen Pseudomonas syringae. PLANTS (BASEL, SWITZERLAND) 2023; 12:plants12091765. [PMID: 37176823 PMCID: PMC10181079 DOI: 10.3390/plants12091765] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 04/01/2023] [Accepted: 04/14/2023] [Indexed: 05/15/2023]
Abstract
Plant diseases caused by the pathogen Pseudomonas syringae are serious problems for various plant species worldwide. Accurate detection and diagnosis of P. syringae infections are critical for the effective management of these plant diseases. In this review, we summarize the current methods for the detection and diagnosis of P. syringae, including traditional techniques such as culture isolation and microscopy, and relatively newer techniques such as PCR and ELISA. It should be noted that each method has its advantages and disadvantages, and the choice of each method depends on the specific requirements, resources of each laboratory, and field settings. We also discuss the future trends in this field, such as the need for more sensitive and specific methods to detect the pathogens at low concentrations and the methods that can be used to diagnose P. syringae infections that are co-existing with other pathogens. Modern technologies such as genomics and proteomics could lead to the development of new methods of highly accurate detection and diagnosis based on the analysis of genetic and protein markers of the pathogens. Furthermore, using machine learning algorithms to analyze large data sets could yield new insights into the biology of P. syringae and novel diagnostic strategies. This review could enhance our understanding of P. syringae and help foster the development of more effective management techniques of the diseases caused by related pathogens.
Collapse
Affiliation(s)
- Piao Yang
- Department of Plant Pathology, College of Food, Agricultural, and Environmental Science, The Ohio State University, Columbus, OH 43210, USA
| | - Lijing Zhao
- Department of Plant Pathology, College of Food, Agricultural, and Environmental Science, The Ohio State University, Columbus, OH 43210, USA
| | - Yu Gary Gao
- OSU South Centers, The Ohio State University, 1864 Shyville Road, Piketon, OH 45661, USA
- Department of Extension, College of Food, Agricultural, and Environmental Sciences, The Ohio State University, Columbus, OH 43210, USA
| | - Ye Xia
- Department of Plant Pathology, College of Food, Agricultural, and Environmental Science, The Ohio State University, Columbus, OH 43210, USA
| |
Collapse
|
14
|
Role of Resuscitation Promoting Factor-like Protein from Nocardiopsis halophila. Microorganisms 2023; 11:microorganisms11020485. [PMID: 36838450 PMCID: PMC9966590 DOI: 10.3390/microorganisms11020485] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 02/11/2023] [Accepted: 02/13/2023] [Indexed: 02/18/2023] Open
Abstract
Resuscitation promoting factors (Rpf), a class of proteins secreted by gram-positive bacteria including actinobacteria, promote the resuscitation of dormant bacteria and spore germination. Here, we describe the reconstitution of the resuscitation promoting activity of the Rpf protein from Nocardiopsis halophila CGMCC 4.1195Tin vitro and in vivo. The Rpf protein was expressed in the host Escherichia coli BL21 codon plus (DE3) and was confirmed to have a significant resuscitation effect on the viable but non-culturable (VBNC) N. halophila. Subsequently, the rpf gene of N. halophila was knocked out. We found that the growth rate of the mutant strain (Δrpf) was slower than that of the wild strain, and the former produced significantly shorter spores than the wild-type strain. Our results confirmed the activity of the Rpf protein in N. halophila to promote dormant bacteria resuscitation. This study will lay the foundation for the application of the Rpf protein from N. halophila to exploit actinomycetes resources.
Collapse
|
15
|
Nisar MA, Ross KE, Brown MH, Bentham R, Best G, Whiley H. Detection and quantification of viable but non-culturable Legionella pneumophila from water samples using flow cytometry-cell sorting and quantitative PCR. Front Microbiol 2023; 14:1094877. [PMID: 36793878 PMCID: PMC9922708 DOI: 10.3389/fmicb.2023.1094877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 01/03/2023] [Indexed: 02/03/2023] Open
Abstract
Legionella pneumophila is a waterborne pathogen and, as the causative agent of Legionnaires' disease, a significant public health concern. Exposure to environmental stresses, and disinfection treatments, promotes the formation of resistant and potentially infectious viable but non-culturable (VBNC) Legionella. The management of engineered water systems to prevent Legionnaires' disease is hindered by the presence of VBNC Legionella that cannot be detected using the standard culture (ISO11731:2017-05) and quantitative polymerase reaction (ISO/TS12869:2019) methods. This study describes a novel method to quantify VBNC Legionella from environmental water samples using a "viability based flow cytometry-cell sorting and qPCR" (VFC + qPCR) assay. This protocol was then validated by quantifying the VBNC Legionella genomic load from hospital water samples. The VBNC cells were unable to be cultured on Buffered Charcoal Yeast Extract (BCYE) agar; however, their viability was confirmed through their ATP activity and ability to infect amoeba hosts. Subsequently, an assessment of the ISO11731:2017-05 pre-treatment procedure demonstrated that acid or heat treatment cause underestimation of alive Legionella population. Our results showed that these pre-treatment procedures induce culturable cells to enter a VBNC state. This may explain the observed insensitivity and lack of reproducibility often observed with the Legionella culture method. This study represents the first time that flow cytometry-cell sorting in conjunction with a qPCR assay has been used as a rapid and direct method to quantify VBNC Legionella from environmental sources. This will significantly improve future research evaluating Legionella risk management approaches for the control of Legionnaires' disease.
Collapse
Affiliation(s)
- Muhammad Atif Nisar
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Kirstin E. Ross
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Melissa H. Brown
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Richard Bentham
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia
| | - Giles Best
- College of Medicine and Public Health, Flinders University, Bedford Park, SA, Australia,Flow Cytometry Facility, Flinders University, Bedford Park, SA, Australia
| | - Harriet Whiley
- College of Science and Engineering, Flinders University, Bedford Park, SA, Australia,*Correspondence: Harriet Whiley, ✉
| |
Collapse
|
16
|
Siatkowski M, Dahyot S, Pestel-Caron M, Boyer S. Performance evaluation of UF-4000 body fluid mode for detection of bacteria in body fluids. Clin Chim Acta 2023; 538:9-14. [PMID: 36374847 DOI: 10.1016/j.cca.2022.10.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 10/07/2022] [Accepted: 10/25/2022] [Indexed: 01/12/2023]
Abstract
BACKGROUND Microbiological analysis of body fluids (BF) provides important information for diagnosis of infection. We evaluated the analytical performance of bacterial count by UF-4000 BF mode for ascitic, cerebrospinal, pleural, synovial and continuous ambulatory peritoneal dialysis fluids compared to classical microbiological procedure (direct Gram staining and culture). MATERIALS AND METHODS For the 1,734 BF analyzed, distribution of UF-4000 bacterial count was analyzed according to the level of growth culture and results were compared using Mann-Whitney test. ROC curves analysis allowed to define the best cut-off value to predict or exclude positive culture for each type of BF. RESULTS UF-4000 bacterial counts were significantly lower in sterile than in infected BFs (p < 0.00001) and correlated with the level of growth on culture. The ROC curves of bacteria/μL and culture positivity yielded area under the curve >0.80 for each type of BF. Optimal cut-offs were chosen with excellent statistical parameters (sensitivity ranging from 0.70 to 0.86, specificity from 0.78 to 0.98, negative predictive value >0.95 and Youden index >0.55). CONCLUSION For BF, UF-4000 bacterial count correlate with culture results and is a discriminative method enhancing detection of microbiological etiology. It could be used as a screening method based on the cut-off values proposed in this study.
Collapse
Affiliation(s)
| | - Sandrine Dahyot
- Normandie Univ, UNIROUEN, UNICAEN, Inserm U 1311, CHU Rouen, Department of Microbiology, F-76000 Rouen, France
| | - Martine Pestel-Caron
- Normandie Univ, UNIROUEN, UNICAEN, Inserm U 1311, CHU Rouen, Department of Microbiology, F-76000 Rouen, France
| | - Sophie Boyer
- CHU Rouen, Department of Microbiology, F-76000 Rouen, France.
| |
Collapse
|
17
|
Trinh KTL, Lee NY. Recent Methods for the Viability Assessment of Bacterial Pathogens: Advances, Challenges, and Future Perspectives. Pathogens 2022; 11:1057. [PMID: 36145489 PMCID: PMC9500772 DOI: 10.3390/pathogens11091057] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 09/14/2022] [Accepted: 09/15/2022] [Indexed: 11/28/2022] Open
Abstract
Viability assessment is a critical step in evaluating bacterial pathogens to determine infectious risks to public health. Based on three accepted viable criteria (culturability, metabolic activity, and membrane integrity), current viability assessments are categorized into three main strategies. The first strategy relies on the culturability of bacteria. The major limitation of this strategy is that it cannot detect viable but nonculturable (VBNC) bacteria. As the second strategy, based on the metabolic activity of bacteria, VBNC bacteria can be detected. However, VBNC bacteria sometimes can enter a dormant state that allows them to silence reproduction and metabolism; therefore, they cannot be detected based on culturability and metabolic activity. In order to overcome this drawback, viability assessments based on membrane integrity (third strategy) have been developed. However, these techniques generally require multiple steps, bulky machines, and laboratory technicians to conduct the tests, making them less attractive and popular applications. With significant advances in microfluidic technology, these limitations of current technologies for viability assessment can be improved. This review summarized and discussed the advances, challenges, and future perspectives of current methods for the viability assessment of bacterial pathogens.
Collapse
Affiliation(s)
- Kieu The Loan Trinh
- Department of Industrial Environmental Engineering, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si 13120, Korea
| | - Nae Yoon Lee
- Department of BioNano Technology, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si 13120, Korea
| |
Collapse
|
18
|
Puntillo M, Segli F, Champagne CP, Raymond Y, Vinderola G. Functional Microbes and Their Incorporation into Foods and Food Supplements: Probiotics and Postbiotics. Annu Rev Food Sci Technol 2022; 13:385-407. [PMID: 35333590 DOI: 10.1146/annurev-food-052720-011545] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Life expectancy has dramatically increased over the past 200 years, but modern life factors such as environmental exposure, antibiotic overuse, C-section deliveries, limited breast-feeding, and diets poor in fibers and microbes could be associated with the rise of noncommunicable diseases such as overweight, obesity, diabetes, food allergies, and colorectal cancer as well as other conditions such as mental disorders. Microbial interventions that range from transplanting a whole undefined microbial community from a healthy gut to an ill one, e.g., so-called fecal microbiota transplantation or vaginal seeding, to the administration of selected well-characterized microbes, either live (probiotics) or not (postbiotics), with efficacy demonstrated in clinical trials, may be effective tools to treat or prevent acute and chronic diseases that humans still face, enhancing the quality of life.
Collapse
Affiliation(s)
- Melisa Puntillo
- Instituto de Lactología Industrial (CONICET-UNL), Facultad de Ingeniería Química, Universidad Nacional del Litoral, Santa Fe, Argentina;
| | - Franco Segli
- Centro de Referencia para Lactobacilos (CERELA-CONICET), Tucumán, Argentina
| | - Claude P Champagne
- Research and Development Centre of Saint-Hyacinthe, Agriculture and Agri-Food Canada, Saint-Hyacinthe, Québec, Canada.,Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Université Laval, Québec, Canada
| | - Yves Raymond
- Research and Development Centre of Saint-Hyacinthe, Agriculture and Agri-Food Canada, Saint-Hyacinthe, Québec, Canada.,Institut sur la Nutrition et les Aliments Fonctionnels (INAF), Université Laval, Québec, Canada
| | - Gabriel Vinderola
- Instituto de Lactología Industrial (CONICET-UNL), Facultad de Ingeniería Química, Universidad Nacional del Litoral, Santa Fe, Argentina;
| |
Collapse
|
19
|
Auty JM, Jenkins CH, Hincks J, Straatman-Iwanowska AA, Allcock N, Turapov O, Galyov EE, Harding SV, Mukamolova GV. Generation of Distinct Differentially Culturable Forms of Burkholderia following Starvation at Low Temperature. Microbiol Spectr 2022; 10:e0211021. [PMID: 34985335 PMCID: PMC8729786 DOI: 10.1128/spectrum.02110-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 12/04/2021] [Indexed: 11/20/2022] Open
Abstract
Bacteria have developed unique mechanisms to adapt to environmental stresses and challenges of the immune system. Here, we report that Burkholderia pseudomallei, the causative agent of melioidosis, and its laboratory surrogate, Burkholderia thailandensis, utilize distinct mechanisms for surviving starvation at different incubation temperatures. At 21°C, Burkholderia are present as short rods which can rapidly reactivate and form colonies on solid media. At 4°C, Burkholderia convert into coccoid forms that cannot be cultured on solid agar but can be resuscitated in liquid media supplemented with supernatant obtained from logarithmic phase cultures of B. thailandensis, or catalase and Tween 80, thus displaying characteristics of differentially culturable bacteria (DCB). These DCB have low intensity fluorescence when stained with SYTO 9, have an intact cell membrane (propidium iodide negative), and contain 16S rRNA at levels comparable with growing cells. We also present evidence that lytic transglycosylases, a family of peptidoglycan-remodeling enzymes, are involved in the generation of coccoid forms and their resuscitation to actively growing cells. A B. pseudomallei ΔltgGCFD mutant with four ltg genes deleted did not produce coccoid forms at 4°C and could not be resuscitated in the liquid media evaluated. Our findings provide insights into the adaptation of Burkholderia to nutrient limitation and the generation of differentially culturable bacteria. IMPORTANCE Bacterial pathogens exhibit physiologically distinct forms that enable their survival in an infected host, the environment and following exposure to antimicrobial agents. B. pseudomallei causes the disease melioidosis, which has a high mortality rate and is difficult to treat with antibiotics. The bacterium is endemic to several countries and detected in high abundance in the environment. Here, we report that during starvation at low temperature, B. pseudomallei produces coccoid forms that cannot grow in standard media and which, therefore, can be challenging to detect using common tools. We provide evidence that the formation of these cocci is mediated by cell wall-specialized enzymes and lytic transglycosylases, and that resuscitation of these forms occurs following the addition of catalase and Tween 80. Our findings have important implications for the disease control and detection of B. pseudomallei, an agent of both public health and defense interest.
Collapse
Affiliation(s)
- Joss M. Auty
- Department of Respiratory Sciences, University of Leicester, Leicester, United Kingdom
| | - Christopher H. Jenkins
- Defence Science and Technology Laboratory, Chemical, Biological and Radiological Division, Porton Down, Salisbury, Wiltshire, United Kingdom
| | - Jennifer Hincks
- FACS Facility Core Biotechnology Services, University of Leicester, Leicester, United Kingdom
| | - Anna A. Straatman-Iwanowska
- Electron Microscopy Facility, Core Biotechnology Services, University of Leicester, Leicester, United Kingdom
| | - Natalie Allcock
- Electron Microscopy Facility, Core Biotechnology Services, University of Leicester, Leicester, United Kingdom
| | - Obolbek Turapov
- Department of Respiratory Sciences, University of Leicester, Leicester, United Kingdom
| | - Edouard E. Galyov
- Department of Genetics and Genome Biology, University of Leicester, Leicester, United Kingdom
| | - Sarah V. Harding
- Department of Respiratory Sciences, University of Leicester, Leicester, United Kingdom
- Defence Science and Technology Laboratory, Chemical, Biological and Radiological Division, Porton Down, Salisbury, Wiltshire, United Kingdom
| | - Galina V. Mukamolova
- Department of Respiratory Sciences, University of Leicester, Leicester, United Kingdom
| |
Collapse
|
20
|
Jiao Z, Yang J, Long X, Lu Y, Guo Z, Peng Y, Huang X, Yin Y, Song C, Zhang P. CRISPR/Cas12a-Assisted Visual Logic-Gate Detection of Pathogenic Microorganisms Based on Water-Soluble DNA-Binding AIEgens. Front Chem 2022; 9:801972. [PMID: 35096768 PMCID: PMC8795674 DOI: 10.3389/fchem.2021.801972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 12/14/2021] [Indexed: 11/20/2022] Open
Abstract
Here, we developed a rapid, visual and double-checked Logic Gate detection platform for detection of pathogenic microorganisms by aggregation-induced emission luminogens (AIEgens) in combination with Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)/CRISPR associated (Cas). DNA light-up AIEgens (1,1,2,2-tetrakis[4-(2-bromo-ethoxy) phenyl]ethene, TTAPE) was non-emissive but the emission was turned on in the presence of large amount of DNA produced by recombinase polymerase amplification (RPA). When CRISPR/Cas12a was added, all long-stranded DNA were cut leading to the emission quenched. Thus, a method that can directly observe the emission changes with the naked eye has been successfully constructed. The detection is speedy within only 20 min, and has strong specificity to the target. The result can be judged by Logic Gate. Only when the output signal is (1,0), does it represent the presence of pathogenic microorganisms in the test object. Finally, the method was applied to the detect pathogenic microorganisms in environmental water samples, which proved that this method has high selectivity, specificity and applicability for the detection of pathogenic microorganisms in environmental water samples.
Collapse
Affiliation(s)
- Zhe Jiao
- School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, China
| | - Jialing Yang
- School of Environment and Civil Engineering, Dongguan University of Technology, Dongguan, China
| | - Xiaojuan Long
- Guangdong Dongguan Ecological and Environmental Monitoring Station, Dongguan, China
| | - Yingfang Lu
- Guangdong Dongguan Ecological and Environmental Monitoring Station, Dongguan, China
- *Correspondence: Yingfang Lu, ; Xuelin Huang, ; Chao Song, ; Pengfei Zhang,
| | - Zongning Guo
- Huangpu Customs District Technology Center, Dongguan, China
| | - Yonglin Peng
- Pinete (Zhongshan) Biotechnology Co., Ltd., Zhongshan, China
| | - Xuelin Huang
- Huangpu Customs District Technology Center, Dongguan, China
- *Correspondence: Yingfang Lu, ; Xuelin Huang, ; Chao Song, ; Pengfei Zhang,
| | - Yi Yin
- Pearl River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou, China
| | - Chao Song
- Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
- Key Laboratory of Control of Quality and Safety for Aquatic Products, Ministry of Agriculture and Rural Affairs, Beijing, China
- *Correspondence: Yingfang Lu, ; Xuelin Huang, ; Chao Song, ; Pengfei Zhang,
| | - Pengfei Zhang
- Guangdong Key Laboratory of Nanomedicine, Shenzhen Engineering Laboratory of Nanomedicine and Nanoformulations, CAS Key Laboratory of Health Informatics, Institute of Biomedicine and Biotechnology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
- *Correspondence: Yingfang Lu, ; Xuelin Huang, ; Chao Song, ; Pengfei Zhang,
| |
Collapse
|
21
|
Vieco-Saiz N, Belguesmia Y, Raspoet R, Auclair E, Padgett C, Bailey C, Gancel F, Drider D. Protective Effects of Novel Lactobacillaceae Strains Isolated from Chicken Caeca against Necrotic Enteritis Infection: In Vitro and In Vivo Evidences. Microorganisms 2022; 10:152. [PMID: 35056601 PMCID: PMC8780607 DOI: 10.3390/microorganisms10010152] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 01/07/2022] [Accepted: 01/10/2022] [Indexed: 01/27/2023] Open
Abstract
The present study aimed to show the benefits of novel lactic acid bacteria (LAB) strains isolated from the caeca of healthy chickens. These novel strains, identified as Limosilactobacillus reuteri and Ligilactobacillus salivarius, displayed high levels of lactic acid production, capability of biofilm formation, high aggregation and adhesion scores, and significant survival rates under conditions mimicking the chicken gastrointestinal tract (GIT). In addition, these novel Lactobacillaceae isolates were neither hemolytic nor cytotoxic. In vivo trials were able to establish their ability to reduce necrotic enteritis. Notably, a significant weight gain was registered, on day 10 of treatment, in the group of chickens fed with a mixture of L. reuteri ICVB416 and L. salivarius ICVB430 strains, as compared with the control group. This group has also shown a reduced number of lesions in the gut compared with other infected chicken groups. This study provides in vitro and in vivo evidence supporting the benefits of these novel Lactobacillaceae isolates for their use in poultry livestock as protective cultures to control the bacterial necrotic enteritis (NE) Clostridium perfringens.
Collapse
Affiliation(s)
- Nuria Vieco-Saiz
- UMR Transfrontalière BioEcoAgro1158, Univ. Lille, INRAE, Univ. Liège, UPJV, YNCREA, Univ. Artois, Univ. Littoral Côte d’Opale, ICV—Institut Charles Viollette, F-59000 Lille, France; (N.V.-S.); (Y.B.); (F.G.)
| | - Yanath Belguesmia
- UMR Transfrontalière BioEcoAgro1158, Univ. Lille, INRAE, Univ. Liège, UPJV, YNCREA, Univ. Artois, Univ. Littoral Côte d’Opale, ICV—Institut Charles Viollette, F-59000 Lille, France; (N.V.-S.); (Y.B.); (F.G.)
| | - Ruth Raspoet
- Phileo Lesaffre Animal Care, 137 Rue Gabriel Péri, F-59700 Marcq-en-Barœul, France; (R.R.); (E.A.)
| | - Eric Auclair
- Phileo Lesaffre Animal Care, 137 Rue Gabriel Péri, F-59700 Marcq-en-Barœul, France; (R.R.); (E.A.)
| | - Connor Padgett
- Phileo by Lesaffre, 7475 W Main St., Milwaukee, WI 53214, USA;
- Department of Poultry Science, Texas A&M University, 101 Kleberg Center, 2472 TAMU, College Station, TX 77845, USA;
| | - Christopher Bailey
- Department of Poultry Science, Texas A&M University, 101 Kleberg Center, 2472 TAMU, College Station, TX 77845, USA;
| | - Frédérique Gancel
- UMR Transfrontalière BioEcoAgro1158, Univ. Lille, INRAE, Univ. Liège, UPJV, YNCREA, Univ. Artois, Univ. Littoral Côte d’Opale, ICV—Institut Charles Viollette, F-59000 Lille, France; (N.V.-S.); (Y.B.); (F.G.)
| | - Djamel Drider
- UMR Transfrontalière BioEcoAgro1158, Univ. Lille, INRAE, Univ. Liège, UPJV, YNCREA, Univ. Artois, Univ. Littoral Côte d’Opale, ICV—Institut Charles Viollette, F-59000 Lille, France; (N.V.-S.); (Y.B.); (F.G.)
| |
Collapse
|
22
|
Copper(II) and silver(I)-1,10-phenanthroline-5,6-dione complexes interact with double-stranded DNA: further evidence of their apparent multi-modal activity towards Pseudomonas aeruginosa. J Biol Inorg Chem 2022; 27:201-213. [PMID: 35006347 PMCID: PMC8840922 DOI: 10.1007/s00775-021-01922-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Accepted: 12/13/2021] [Indexed: 01/04/2023]
Abstract
Tackling microbial resistance requires continuous efforts for the development of new molecules with novel mechanisms of action and potent antimicrobial activity. Our group has previously identified metal-based compounds, [Ag(1,10-phenanthroline-5,6-dione)2]ClO4 (Ag-phendione) and [Cu(1,10-phenanthroline-5,6-dione)3](ClO4)2.4H2O (Cu-phendione), with efficient antimicrobial action against multidrug-resistant species. Herein, we investigated the ability of Ag-phendione and Cu-phendione to bind with double-stranded DNA using a combination of in silico and in vitro approaches. Molecular docking revealed that both phendione derivatives can interact with the DNA by hydrogen bonding, hydrophobic and electrostatic interactions. Cu-phendione exhibited the highest binding affinity to either major (− 7.9 kcal/mol) or minor (− 7.2 kcal/mol) DNA grooves. In vitro competitive quenching assays involving duplex DNA with Hoechst 33258 or ethidium bromide demonstrated that Ag-phendione and Cu-phendione preferentially bind DNA in the minor grooves. The competitive ethidium bromide displacement technique revealed Cu-phendione has a higher binding affinity to DNA (Kapp = 2.55 × 106 M−1) than Ag-phendione (Kapp = 2.79 × 105 M−1) and phendione (Kapp = 1.33 × 105 M−1). Cu-phendione induced topoisomerase I-mediated DNA relaxation of supercoiled plasmid DNA. Moreover, Cu-phendione was able to induce oxidative DNA injuries with the addition of free radical scavengers inhibiting DNA damage. Ag-phendione and Cu-phendione avidly displaced propidium iodide bound to DNA in permeabilized Pseudomonas aeruginosa cells in a dose-dependent manner as judged by flow cytometry. The treatment of P. aeruginosa with bactericidal concentrations of Cu-phendione (15 µM) induced DNA fragmentation as visualized by either agarose gel or TUNEL assays. Altogether, these results highlight a possible novel DNA-targeted mechanism by which phendione-containing complexes, in part, elicit toxicity toward the multidrug-resistant pathogen P. aeruginosa.
Collapse
|
23
|
The Concentration-Dependent Effects of Essential Oils on the Growth of Fusarium graminearum and Mycotoxins Biosynthesis in Wheat and Maize Grain. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12010473] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The presence of Fusarium fungi and their toxic metabolites in agricultural crops contributes to significant quantitative and qualitative losses of crops, causing a direct threat to human and animal health and life. Modern strategies for reducing the level of fungi and mycotoxins in the food chain tend to rely on natural methods, including plant substances. Essential oils (EOs), due to their complex chemical composition, show high biological activity, including fungistatic properties, which means that they exhibit high potential as a biological plant protection factor. The aim of this study was to determine the fungistatic activity of three EOs against F. graminearum, and the reduction of mycotoxin biosynthesis in corn and wheat grain. All tested EOs effectively suppressed the growth of F. graminearum in concentrations of 5% and 10%. Cinnamon and verbena EOs also effectively reduced the ergosterol (ERG) content in both grains at the concentration of 1%, while at the 0.1% EO concentration, the reduction in the ERG amount depended on the EO type as well as on the grain. The degree of zearalenone (ZEA) reduction was consistent with the inhibition of ERG biosynthesis, while the reduction in deoxynivalenol (DON) was not consistent with this parameter.
Collapse
|
24
|
Zand E, Froehling A, Schoenher C, Zunabovic-Pichler M, Schlueter O, Jaeger H. Potential of Flow Cytometric Approaches for Rapid Microbial Detection and Characterization in the Food Industry-A Review. Foods 2021; 10:3112. [PMID: 34945663 PMCID: PMC8701031 DOI: 10.3390/foods10123112] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 11/14/2021] [Accepted: 11/16/2021] [Indexed: 12/11/2022] Open
Abstract
As microbial contamination is persistent within the food and bioindustries and foodborne infections are still a significant cause of death, the detection, monitoring, and characterization of pathogens and spoilage microorganisms are of great importance. However, the current methods do not meet all relevant criteria. They either show (i) inadequate sensitivity, rapidity, and effectiveness; (ii) a high workload and time requirement; or (iii) difficulties in differentiating between viable and non-viable cells. Flow cytometry (FCM) represents an approach to overcome such limitations. Thus, this comprehensive literature review focuses on the potential of FCM and fluorescence in situ hybridization (FISH) for food and bioindustry applications. First, the principles of FCM and FISH and basic staining methods are discussed, and critical areas for microbial contamination, including abiotic and biotic surfaces, water, and air, are characterized. State-of-the-art non-specific FCM and specific FISH approaches are described, and their limitations are highlighted. One such limitation is the use of toxic and mutagenic fluorochromes and probes. Alternative staining and hybridization approaches are presented, along with other strategies to overcome the current challenges. Further research needs are outlined in order to make FCM and FISH even more suitable monitoring and detection tools for food quality and safety and environmental and clinical approaches.
Collapse
Affiliation(s)
- Elena Zand
- Department of Food Science and Technology, Institute of Food Technology, University of Natural Resources and Life Sciences Vienna (BOKU), 1190 Vienna, Austria;
| | - Antje Froehling
- Leibniz Institute for Agricultural Engineering and Bioeconomy, Quality and Safety of Food and Feed, 14469 Potsdam, Germany; (A.F.); (O.S.)
| | - Christoph Schoenher
- Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Life Sciences, 1190 Vienna, Austria; (C.S.); (M.Z.-P.)
| | - Marija Zunabovic-Pichler
- Institute of Sanitary Engineering and Water Pollution Control, University of Natural Resources and Life Sciences, 1190 Vienna, Austria; (C.S.); (M.Z.-P.)
| | - Oliver Schlueter
- Leibniz Institute for Agricultural Engineering and Bioeconomy, Quality and Safety of Food and Feed, 14469 Potsdam, Germany; (A.F.); (O.S.)
| | - Henry Jaeger
- Department of Food Science and Technology, Institute of Food Technology, University of Natural Resources and Life Sciences Vienna (BOKU), 1190 Vienna, Austria;
| |
Collapse
|
25
|
Klasinc R, Reiter M, Digruber A, Tschulenk W, Walter I, Kirschner A, Spittler A, Stockinger H. A Novel Flow Cytometric Approach for the Quantification and Quality Control of Chlamydia trachomatis Preparations. Pathogens 2021; 10:1617. [PMID: 34959572 PMCID: PMC8706156 DOI: 10.3390/pathogens10121617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 12/07/2021] [Accepted: 12/09/2021] [Indexed: 11/27/2022] Open
Abstract
Chlamydia trachomatis is an obligate intracellular pathogenic bacterium with a biphasic developmental cycle manifesting two distinct morphological forms: infectious elementary bodies (EBs) and replicative intracellular reticulate bodies (RBs). Current standard protocols for quantification of the isolates assess infectious particles by titering inclusion-forming units, using permissive cell lines, and analyzing via immunofluorescence. Enumeration of total particle counts is achieved by counting labeled EBs/RBs using a fluorescence microscope. Both methods are time-consuming with a high risk of observer bias. For a better assessment of C. trachomatis preparations, we developed a simple and time-saving flow cytometry-based workflow for quantifying small particles, such as EBs with a size of 300 nm. This included optimization of gain and threshold settings with the addition of a neutral density filter for small-particle discrimination. The nucleic acid dye SYBR® Green I (SGI) was used together with propidium iodide and 5(6)-carboxyfluorescein diacetate to enumerate and discriminate between live and dead bacteria. We found no significant differences between the direct particle count of SGI-stained C. trachomatis preparations measured by microscopy or flow cytometry (p > 0.05). Furthermore, we completed our results by introducing a cell culture-independent viability assay. Our measurements showed very good reproducibility and comparability to the existing state-of-the-art methods, indicating that the evaluation of C. trachomatis preparations by flow cytometry is a fast and reliable method. Thus, our method facilitates an improved assessment of the quality of C. trachomatis preparations for downstream applications.
Collapse
Affiliation(s)
- Romana Klasinc
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria; (M.R.); (A.K.); (H.S.)
| | - Michael Reiter
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria; (M.R.); (A.K.); (H.S.)
| | - Astrid Digruber
- Institute of Microbiology, Department of Pathobiology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria;
| | - Waltraud Tschulenk
- Institute of Morphology, Department of Pathobiology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria; (W.T.); (I.W.)
| | - Ingrid Walter
- Institute of Morphology, Department of Pathobiology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria; (W.T.); (I.W.)
| | - Alexander Kirschner
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria; (M.R.); (A.K.); (H.S.)
- Division Water Quality & Health, Department Pharmacology, Physiology and Microbiology, Karl Landsteiner University of Health Sciences, 3500 Krems, Austria
| | - Andreas Spittler
- Core Facility Flow Cytometry and Department of Surgery, Research Laboratories, Medical University of Vienna, 1090 Vienna, Austria;
| | - Hannes Stockinger
- Institute for Hygiene and Applied Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, 1090 Vienna, Austria; (M.R.); (A.K.); (H.S.)
| |
Collapse
|
26
|
Mao G, Wang Y, Hammes F. Automated flow cytometry as a flexible tool for comparing disinfection characteristics of indigenous bacterial communities and pure cultures. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 225:112799. [PMID: 34555718 DOI: 10.1016/j.ecoenv.2021.112799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 08/23/2021] [Accepted: 09/15/2021] [Indexed: 06/13/2023]
Abstract
Bacterial inactivation efficiency of chlorine varies with organisms and environmental conditions. The comparability of different samples/studies, especially comparing indigenous bacterial communities with pure cultures, is impeded by inconsistent experimental conditions and analytical methods used in various studies. We tested a novel 96-well plate FCM experimental and automated analytical approach, where bacterial communities and pure cultures were suspended in the same natural water matrix prior to chlorination directly in the plate. We demonstrated the ability to rapidly monitor the efficiency of 32 different combinations of chlorine concentration and time (i.e. chlorine exposure) on bacterial pure cultures and indigenous aquatic communities, which enabled correct comparison of the data from different samples under the exact same experimental conditions. In this study, the 96-well plate automated FCM approach enabled large sets (896) of independent chlorination experiments to be carried out in a short time period. To our knowledge, this is the largest dataset of chlorination experiments which consumed least time (within 18 h after sampling) until now. Staining with SYBR Green I (SG) and SG combined with propidium iodide (SGPI) was used to assess cellular damage during chlorination. The results showed that with the same chlorine exposure, a higher chlorine concentration with a shorter contact time is favorable for inactivation of bacteria. Our research provides a promising framework to compare disinfection characteristics of various microorganism and can be further developed to diagnose effect of antimicrobial products.
Collapse
Affiliation(s)
- Guannan Mao
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China; Department of Environmental Microbiology, Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf 8600, Switzerland; State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Yingying Wang
- Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education), Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China.
| | - Frederik Hammes
- Department of Environmental Microbiology, Eawag: Swiss Federal Institute of Aquatic Science and Technology, Dübendorf 8600, Switzerland.
| |
Collapse
|
27
|
|
28
|
Wang L, Ye C, Guo L, Chen C, Kong X, Chen Y, Shu L, Wang P, Yu X, Fang J. Assessment of the UV/Chlorine Process in the Disinfection of Pseudomonas aeruginosa: Efficiency and Mechanism. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:9221-9230. [PMID: 34138551 DOI: 10.1021/acs.est.1c00645] [Citation(s) in RCA: 69] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
UV irradiation and chlorination have been widely used for water disinfection. However, there are some limitations, such as the risk of generating viable but nonculturable bacteria and bacteria reactivation when using UV irradiation or chlorination alone. This study comprehensively evaluated the feasibility of the UV/chlorine process in drinking water disinfection, and Pseudomonas aeruginosa was selected as the target microorganism. The number of culturable cells was effectively reduced by more than 5 orders of magnitude (5-log10) after UV, chlorine, and UV/chlorine treatments. However, intact and VBNC cells were detected at 103 to 104 cells/mL after UV and chlorine treatments, whereas they were undetectable after UV/chlorine treatment due to the primary contribution of reactive chlorine species (Cl•, Cl2•-, and ClO•). After UV/chlorine treatment, the metabolic activity determined using single cell Raman spectroscopy was much lower than that after UV. The level of toxic opr gene in P. aeruginosa decreased by more than 99% after UV/chlorine treatment. Importantly, bacterial dark reactivation was completely suppressed by UV/chlorine treatment but not UV or chlorination. This study suggests that the UV/chlorine treatment can completely damage bacteria and is promising for pathogen inactivation to overcome the limitations of UV and chlorine treatments alone.
Collapse
Affiliation(s)
- Liping Wang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Chengsong Ye
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, P. R. China
| | - Lizheng Guo
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, P. R. China
| | - Chunyan Chen
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Xiujuan Kong
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Yaoqing Chen
- School of Public Health, Shenzhen, Sun Yat-Sen University, Shenzhen 510000, P. R. China
| | - Longfei Shu
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| | - Peng Wang
- Department of Civil and Environmental Engineering, Hong Kong Polytechnic University, Kowloon 999077, Hong Kong, P.R. China
| | - Xin Yu
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, P. R. China
| | - Jingyun Fang
- Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, School of Environmental Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, P. R. China
| |
Collapse
|
29
|
Sawada T, Katayama M, Takatani S, Ohiro Y. Early detection of drug-resistant Streptococcus pneumoniae and Haemophilus influenzae by quantitative flow cytometry. Sci Rep 2021; 11:2873. [PMID: 33536509 PMCID: PMC7859230 DOI: 10.1038/s41598-021-82186-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 01/04/2021] [Indexed: 01/30/2023] Open
Abstract
Early detection of drug resistance contributes to combating drug-resistant bacteria and improving patient outcomes. Microbial testing in the laboratory is essential for treating infectious diseases because it can provide critical information related to identifying pathogenic bacteria and their resistance profiles. Despite these clinical requirements, conventional phenotypic testing is time-consuming. Additionally, recent rapid drug resistance tests are not compatible with fastidious bacteria such as Streptococcus and Haemophilus species. In this study, we validated the feasibility of direct bacteria counting using highly sensitive quantitative flow cytometry. Furthermore, by combining flow cytometry and a nucleic acid intercalator, we constructed a highly sensitive method for counting viable fastidious bacteria. These are inherently difficult to measure due to interfering substances from nutrients contained in the medium. Based on the conventional broth microdilution method, our method acquired a few microliter samples in a time series from the same microplate well to exclude the growth curve inconsistency between the samples. Fluorescent staining and flow cytometry measurements were completed within 10 min. Therefore, this approach enabled us to determine antimicrobial resistance for these bacteria within a few hours. Highly sensitive quantitative flow cytometry presents a novel avenue for conducting rapid antimicrobial susceptibility tests.
Collapse
Affiliation(s)
- Takahiro Sawada
- grid.508063.80000 0004 1771 0244Fundamental Research Laboratory, Research and Development Division, Eiken Chemical Co., Ltd., 143 Nogi, Nogimachi, Shimotsuga-gun, Tochigi, 329-0114 Japan
| | - Masayuki Katayama
- grid.419812.70000 0004 1777 4627FCM Development, Business Strategy Development, Sysmex Corporation, 4-4-4 Takatsukadai, Nishi-ku, Kobe, 651-2271 Japan
| | - Shogo Takatani
- grid.419812.70000 0004 1777 4627FCM Development, Business Strategy Development, Sysmex Corporation, 4-4-4 Takatsukadai, Nishi-ku, Kobe, 651-2271 Japan
| | - Yoshiyuki Ohiro
- grid.508063.80000 0004 1771 0244Fundamental Research Laboratory, Research and Development Division, Eiken Chemical Co., Ltd., 143 Nogi, Nogimachi, Shimotsuga-gun, Tochigi, 329-0114 Japan
| |
Collapse
|
30
|
How to Evaluate Non-Growing Cells-Current Strategies for Determining Antimicrobial Resistance of VBNC Bacteria. Antibiotics (Basel) 2021; 10:antibiotics10020115. [PMID: 33530321 PMCID: PMC7912045 DOI: 10.3390/antibiotics10020115] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/19/2021] [Accepted: 01/22/2021] [Indexed: 12/17/2022] Open
Abstract
Thanks to the achievements in sanitation, hygiene practices, and antibiotics, we have considerably improved in our ongoing battle against pathogenic bacteria. However, with our increasing knowledge about the complex bacterial lifestyles and cycles and their plethora of defense mechanisms, it is clear that the fight is far from over. One of these resistance mechanisms that has received increasing attention is the ability to enter a dormancy state termed viable but non-culturable (VBNC). Bacteria that enter the VBNC state, either through unfavorable environmental conditions or through potentially lethal stress, lose their ability to grow on standard enrichment media, but show a drastically increased tolerance against antimicrobials including antibiotics. The inability to utilize traditional culture-based methods represents a considerable experimental hurdle to investigate their increased antimicrobial resistance and impedes the development and evaluation of effective treatments or interventions against bacteria in the VBNC state. Although experimental approaches were developed to detect and quantify VBNCs, only a few have been utilized for antimicrobial resistance screening and this review aims to provide an overview of possible methodological approaches.
Collapse
|
31
|
Gao R, Liao X, Zhao X, Liu D, Ding T. The diagnostic tools for viable but nonculturable pathogens in the food industry: Current status and future prospects. Compr Rev Food Sci Food Saf 2021; 20:2146-2175. [PMID: 33484068 DOI: 10.1111/1541-4337.12695] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Revised: 12/21/2020] [Accepted: 12/28/2020] [Indexed: 12/21/2022]
Abstract
Viable but nonculturable (VBNC) microorganisms have been recognized as pathogenic contaminants in foods and environments. The failure of VBNC cells to form the visible colonies hinders the ability to use conventional media for their detection. Efficient and rapid detection of pathogens in the VBNC state is a prerequisite to ensure the food safety and public health. Despite their nonculturability, VBNC cells have distinct characteristics, such as morphology, metabolism, chemical composition, and gene and protein expression, that have been used as the basis for the development of abundant diagnostic tools. This review covers the current status and advances in various approaches for examining microorganisms in the VBNC state, including but not limited to the methodological aspects, advantages, and drawbacks of each technique. Existing methods, such as direct viable count, SYTO/PI dual staining, and propidium monoazide quantitative polymerase chain reaction (PCR), as well as some techniques with potential to be applied in the future, such as digital PCR, enhanced-surface Raman spectroscopy, and impedance-based techniques, are summarized in depth. Finally, future prospects for the one-step detection of VBNC bacteria are proposed and discussed. We believe that this review can provide more optional methods for researchers and promote the development of rapid, accurate detecting methods, and for inspectors, the diagnostic tools can provide data to undertake risk analysis of VBNC cells.
Collapse
Affiliation(s)
- Rui Gao
- Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xinyu Liao
- Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xihong Zhao
- Research Center for Environmental Ecology and Engineering, Key Laboratory for Green Chemical Process of Ministry of Education, Hubei Key Laboratory of Novel Reactor and Green Chemical Technology, School of Environmental Ecology and Biological Engineering, Wuhan Institute of Technology, Wuhan, China
| | - Donghong Liu
- Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang, China
| | - Tian Ding
- Key Laboratory for Agro-Products Postharvest Handling of Ministry of Agriculture, Zhejiang Key Laboratory for Agro-Food Processing, Department of Food Science and Nutrition, Zhejiang University, Hangzhou, Zhejiang, China
| |
Collapse
|
32
|
Legner M, Jonkman J, Swift D. Evaluating the Effects of Disinfectants on Bacterial Biofilms Using a Microfluidics Flow Cell and Time-Lapse Fluorescence Microscopy. Microorganisms 2020; 8:microorganisms8111837. [PMID: 33266442 PMCID: PMC7700140 DOI: 10.3390/microorganisms8111837] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/11/2020] [Accepted: 11/13/2020] [Indexed: 12/03/2022] Open
Abstract
A commercially available microfluidics flow cell was utilized together with widefield fluorescence microscopy to evaluate the effects of disinfectants on bacterial strains. The flow cell’s inner surface supports the formation of biofilms of numerous bacterial species. The modular setup of the flow cell accessories allows connection to syringes, pumps and collection vials, facilitating aseptic experiments in a controlled fluidics environment which can be documented with precisely timed microscopy imaging. The flow cell is inoculated with a suspension of bacteria in a nutrient medium and incubated for several days allowing bacterial cells to form a biofilm. Shortly before performing an assay, the biofilm is labelled with a dual-fluorescent DNA probe which distinguishes unharmed and damaged bacteria. Then a disinfectant sample (or control) is gently injected and time-lapse imaging is used for quantifying the course of bacterial biomass response. We use a simplified widefield microscopy method that allows intensive recording and quantification of time series of two-dimensional frames for tracking the course of disinfectant action on a variety of microbial strains. This procedure has potential for the rapid evaluation of novel products.
Collapse
Affiliation(s)
- Milos Legner
- Micrylium Laboratories, Toronto, ON M3H 5T5, Canada;
- Correspondence:
| | - James Jonkman
- Advanced Optical Microscopy Facility, University Health Network, Toronto, ON M5G 1L7, Canada;
| | - Dean Swift
- Micrylium Laboratories, Toronto, ON M3H 5T5, Canada;
| |
Collapse
|
33
|
McEvoy B, Lynch M, Rowan NJ. Opportunities for the application of real-time bacterial cell analysis using flow cytometry for the advancement of sterilization microbiology. J Appl Microbiol 2020; 130:1794-1812. [PMID: 33155740 DOI: 10.1111/jam.14876] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 09/10/2020] [Accepted: 09/21/2020] [Indexed: 01/11/2023]
Abstract
Medical devices provide critical care and diagnostic applications through patient contact. Sterility assurance level (SAL) may be defined as the probability of a single viable micro-organism occurring on an item after a sterilization process. Sterilization microbiology often relies upon using an overkill validation method where a 12-log reduction in recalcitrant bacterial endospore population occurs during the process that exploits conventional laboratory-based culture media for enumeration. This timely review explores key assumptions underpinning use of conventional culture-based methods in sterilization microbiology. Consideration is given to how such methods may limit the ability to fully appreciate the inactivation kinetics of a sterilization process such as vaporized hydrogen peroxide (VH2O2) sterilization, and consequently design efficient sterilization processes. Specific use of the real-time flow cytometry (FCM) is described by way of elucidating the practical relevance of these limitation factors with implications and opportunities for the sterilization industry discussed. Application of FCM to address these culture-based limitation factors will inform real-time kinetic inactivation modelling and unlock potential to embrace emerging opportunities for pharma, medical device and sterilization industries including potentially disruptive applications that may involve reduced usage of sterilant.
Collapse
Affiliation(s)
- B McEvoy
- STERIS Applied Sterilization Technologies, IDA Business and Technology Park, Tullamore, Ireland
| | - M Lynch
- Centre for Disinfection, Sterilization and Biosecurity, Athlone Institute of Technology, Athlone, Ireland
| | - N J Rowan
- Centre for Disinfection, Sterilization and Biosecurity, Athlone Institute of Technology, Athlone, Ireland
| |
Collapse
|
34
|
Masoura M, Passaretti P, Overton TW, Lund PA, Gkatzionis K. Use of a model to understand the synergies underlying the antibacterial mechanism of H 2O 2-producing honeys. Sci Rep 2020; 10:17692. [PMID: 33077785 PMCID: PMC7573686 DOI: 10.1038/s41598-020-74937-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Accepted: 10/07/2020] [Indexed: 12/30/2022] Open
Abstract
Honey has been valued as a powerful antimicrobial since ancient times. However, the understanding of the underlying antibacterial mechanism is incomplete. The complexity and variability of honey composition represent a challenge to this scope. In this study, a simple model system was used to investigate the antibacterial effect of, and possible synergies between, the three main stressors present in honey: sugars, gluconic acid, and hydrogen peroxide (H2O2), which result from the enzymatic conversion of glucose on honey dilution. Our results demonstrated that the synergy of H2O2 and gluconic acid is essential for the antibacterial activity of honey. This synergy caused membrane depolarization, destruction of the cell wall, and eventually growth inhibition of E. coli K-12. The presence of H2O2 stimulated the generation of other long-lived ROS in a dose-dependent manner. Sugars caused osmosis-related morphological changes, however, decreased the toxicity of the H2O2/gluconic acid. The susceptibility of catalase and general stress response sigma factor mutants confirmed the synergy of the three stressors, which is enhanced at higher H2O2 concentrations. By monitoring cellular phenotypic changes caused by model honey, we explained how this can be bactericidal even though the antimicrobial compounds which it contains are at non-inhibitory concentrations.
Collapse
Affiliation(s)
- Maria Masoura
- School of Chemical Engineering, University of Birmingham, Birmingham, B15 2SA, UK.,Institute of Microbiology and Infection (IMI), University of Birmingham, Birmingham, B15 2SA, UK
| | - Paolo Passaretti
- School of Chemical Engineering, University of Birmingham, Birmingham, B15 2SA, UK
| | - Tim W Overton
- School of Chemical Engineering, University of Birmingham, Birmingham, B15 2SA, UK
| | - Pete A Lund
- Institute of Microbiology and Infection (IMI), University of Birmingham, Birmingham, B15 2SA, UK
| | - Konstantinos Gkatzionis
- School of Chemical Engineering, University of Birmingham, Birmingham, B15 2SA, UK. .,Department of Food Science and Nutrition, School of the Environment, University of the Aegean, Lemnos, Greece.
| |
Collapse
|
35
|
Techathuvanan C, D'Souza DH. Propidium monoazide for viable Salmonella enterica detection by PCR and LAMP assays in comparison to RNA-based RT-PCR, RT-LAMP, and culture-based assays. J Food Sci 2020; 85:3509-3516. [PMID: 32964461 DOI: 10.1111/1750-3841.15459] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 08/25/2020] [Accepted: 08/26/2020] [Indexed: 12/13/2022]
Abstract
Rapid and sensitive detection of live/infectious foodborne pathogens is urgently needed in order to prevent outbreaks and food recalls. This study aimed to (1) evaluate the incorporation of propidium monoazide (PMA) into PCR or LAMP assays to selectively detect viable Salmonella Enteritidis following sublethal heat or UV treatment, and autoclave sterilization; and (2) compare the detection of PMA-PCR and PMA-LAMP to DNA-based PCR and LAMP (without PMA), RNA-based RT-PCR and RT-LAMP, and culture-based methods. Nucleic acids (DNA or RNA) from 1-mL S. Enteritidis samples were used for PCR, RT-PCR, LAMP, and RT-LAMP assays. Serially diluted samples were plated on Xylose Lysine Tergitol-4 agar for cultural enumeration. Comparable detection of overnight cultured S. Enteritidis was obtained by PMA-PCR, PCR, and RT-PCR, though 1 to 2 log less sensitive than cultural assays. PMA-LAMP and RT-LAMP showed similar detection of overnight cultures, being 1 to 2 log less sensitive than the LAMP assay, and ∼4 log less than culture-based detection. Autoclaved S. Enteritidis did not test positive by RNA-based methods or PMA-PCR, but PMA-LAMP showed detection of 1 log CFU/mL. PMA-PCR and RT-PCR showed comparable detection of sublethal heat-treated cells to cultural assays, while PMA-LAMP showed 1 to 2 log less detection. Our results suggest that PMA-PCR and PMA-LAMP assays are not suitable for selective viable cell detection after UV treatment. While PMA-LAMP assay needs optimization, PMA-PCR shows promise for live/viable S. Enteritidis detection. PMA-PCR shows potential for routine testing in the food industry with results within 1-day, albeit depending on the inactivation method employed.
Collapse
Affiliation(s)
- Chayapa Techathuvanan
- Department of Food Science, University of Tennessee, 2605 River Drive, Knoxville, TN, 37996-4591, U.S.A
| | - Doris Helen D'Souza
- Department of Food Science, University of Tennessee, 2605 River Drive, Knoxville, TN, 37996-4591, U.S.A
| |
Collapse
|
36
|
Sarda-Estève R, Baisnée D, Guinot B, Mainelis G, Sodeau J, O’Connor D, Besancenot JP, Thibaudon M, Monteiro S, Petit JE, Gros V. Atmospheric Biodetection Part I: Study of Airborne Bacterial Concentrations from January 2018 to May 2020 at Saclay, France. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17176292. [PMID: 32872373 PMCID: PMC7504533 DOI: 10.3390/ijerph17176292] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Revised: 08/20/2020] [Accepted: 08/24/2020] [Indexed: 11/16/2022]
Abstract
Background: The monitoring of bioaerosol concentrations in the air is a relevant endeavor due to potential health risks associated with exposure to such particles and in the understanding of their role in climate. In this context, the atmospheric concentrations of bacteria were measured from January 2018 to May 2020 at Saclay, France. The aim of the study was to understand the seasonality, the daily variability, and to identify the geographical origin of airborne bacteria. Methods: 880 samples were collected daily on polycarbonate filters, extracted with purified water, and analyzed using the cultivable method and flow cytometry. A source receptor model was used to identify the origin of bacteria. Results: A tri-modal seasonality was identified with the highest concentrations early in spring and over the summer season with the lowest during the winter season. Extreme changes occurred daily due to rapid changes in meteorological conditions and shifts from clean air masses to polluted ones. Conclusion: Our work points toward bacterial concentrations originating from specific seasonal-geographical ecosystems. During pollution events, bacteria appear to rise from dense urban areas or are transported long distances from their sources. This key finding should drive future actions to better control the dispersion of potential pathogens in the air, like persistent microorganisms originating from contaminated areas.
Collapse
Affiliation(s)
- Roland Sarda-Estève
- Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, Unité mixte de recherche CEA-CNRS-UVSQ, 91190 Saint-Aubin, France; (D.B.); (J.-E.P.); (V.G.)
- Correspondence: ; Tel.: +33-1-69-08-97-47
| | - Dominique Baisnée
- Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, Unité mixte de recherche CEA-CNRS-UVSQ, 91190 Saint-Aubin, France; (D.B.); (J.-E.P.); (V.G.)
| | - Benjamin Guinot
- Laboratoire d’Aérologie, Université Toulouse III, CNRS, UPS, 31400 Toulouse, France;
- Réseau National de Surveillance Aérobiologique, 69690 Brussieu, France; (J.P.B.); (M.T.)
| | - Gediminas Mainelis
- Department of Environmental Sciences, School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, New Brunswick, NJ 08901-8525, USA;
| | - John Sodeau
- Department of Chemistry and Environmental Research Institute, University College Cork, T12 YN60 Cork, Ireland;
| | - David O’Connor
- School of Chemical and Pharmaceutical Sciences, Technological University of Dublin, D06F793 Dublin 6, Ireland;
| | - Jean Pierre Besancenot
- Réseau National de Surveillance Aérobiologique, 69690 Brussieu, France; (J.P.B.); (M.T.)
| | - Michel Thibaudon
- Réseau National de Surveillance Aérobiologique, 69690 Brussieu, France; (J.P.B.); (M.T.)
| | - Sara Monteiro
- Themo Fisher Scientific, 18 avenue de Quebec, 91941 Villebon Courtaboeuf, France;
| | - Jean-Eudes Petit
- Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, Unité mixte de recherche CEA-CNRS-UVSQ, 91190 Saint-Aubin, France; (D.B.); (J.-E.P.); (V.G.)
| | - Valérie Gros
- Laboratoire des Sciences du Climat et de l’Environnement, LSCE/IPSL, Unité mixte de recherche CEA-CNRS-UVSQ, 91190 Saint-Aubin, France; (D.B.); (J.-E.P.); (V.G.)
| |
Collapse
|
37
|
Rozloznik M, Lochmanova A, Chmelar D, Hajek M, Korytkova K, Cisarikova M. Experimental use of flow cytometry to detect bacteria viability after hyperbaric oxygen exposure: Work in progress report. Diving Hyperb Med 2020; 50:152-156. [PMID: 32557417 PMCID: PMC7481111 DOI: 10.28920/dhm50.2.152-156] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 02/23/2020] [Indexed: 11/05/2022]
Abstract
INTRODUCTION Hyperbaric oxygen treatment (HBOT), based on inhaling pure oxygen under elevated ambient pressure, is used as adjuvant intervention to promote healing in infected wounds. Despite extensive clinical evidence of beneficial effects of HBOT in soft tissue infections the mechanism of action remains to be elucidated. The aim of this study was to evaluate the use of flow cytometry as a novel method to assess the viability of pathogenic bacteria after hyperbaric oxygen (HBO) exposure. METHODS Bacterial strains associated with soft tissues infections: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus were exposed to oxygen at 2.8 atmospheres absolute (atm abs) (283.6 kPa) pressure for 45, 90, or 120 min, then stained with propidium iodide and thiazole orange and analysed by flow cytometry. RESULTS Escherichia coli and Staphylococcus aureus showed no change in viability, nor morphology, the viability of Pseudomonas aeruginosa reduced in a dose-dependent manner and Klebsiella pneumoniae also showed dye uptake after HBO. CONCLUSIONS These initial results, indicate diverse sensitivity of bacteria to HBO, and suggest that flow cytometry can be used to monitor viability and morphological changes triggered by HBO exposure in bacteria.
Collapse
Affiliation(s)
- Miroslav Rozloznik
- Department of Biomedical Sciences, Faculty of Medicine, University of Ostrava, Czech Republic
- DAN Europe, Slovensko, Slovakia
- DNB consult, s.r.o, Kezmarok, Slovakia
- Corresponding author: Dr Miroslav Rozloznik, Department of Biomedical Sciences, Medical Faculty, University of Ostrava, Syllabova 19, Ostrava, Czech Republic,
| | - Alexandra Lochmanova
- Department of Biomedical Sciences, Faculty of Medicine, University of Ostrava, Czech Republic
- Public Health Institute, Ostrava, Czech Republic
| | - Dittmar Chmelar
- Department of Biomedical Sciences, Faculty of Medicine, University of Ostrava, Czech Republic
- Czech National Anaerobic Bacteria Reference Laboratory, Faculty of Medicine, University of Ostrava, Czech Republic
| | - Michal Hajek
- Department of Biomedical Sciences, Faculty of Medicine, University of Ostrava, Czech Republic
- Centre for Hyperbaric Medicine, City Hospital, Ostrava, Czech Republic
| | - Karin Korytkova
- Department of Biomedical Sciences, Faculty of Medicine, University of Ostrava, Czech Republic
| | - Monika Cisarikova
- Department of Biomedical Sciences, Faculty of Medicine, University of Ostrava, Czech Republic
| |
Collapse
|
38
|
Schulz F, Andreani J, Francis R, Boudjemaa H, Bou Khalil JY, Lee J, La Scola B, Woyke T. Advantages and Limits of Metagenomic Assembly and Binning of a Giant Virus. mSystems 2020; 5:e00048-20. [PMID: 32576649 PMCID: PMC7311315 DOI: 10.1128/msystems.00048-20] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 05/26/2020] [Indexed: 12/31/2022] Open
Abstract
Giant viruses have large genomes, often within the size range of cellular organisms. This distinguishes them from most other viruses and demands additional effort for the successful recovery of their genomes from environmental sequence data. Here, we tested the performance of genome-resolved metagenomics on a recently isolated giant virus, Fadolivirus, by spiking it into an environmental sample from which two other giant viruses were isolated. At high spike-in levels, metagenome assembly and binning led to the successful genomic recovery of Fadolivirus from the sample. A complementary survey of the major capsid protein indicated the presence of other giant viruses in the sample matrix but did not detect the two isolated from this sample. Our results indicate that genome-resolved metagenomics is a valid approach for the recovery of near-complete giant virus genomes given that sufficient clonal particles are present. However, our data also underline that a vast majority of giant viruses remain currently undetected, even in an era of terabase-scale metagenomics.IMPORTANCE The discovery of large and giant nucleocytoplasmic large DNA viruses (NCLDV) with genomes in the megabase range and equipped with a wide variety of features typically associated with cellular organisms was one of the most unexpected, intriguing, and spectacular breakthroughs in virology. Recent studies suggest that these viruses are highly abundant in the oceans, freshwater, and soil, impact the biology and ecology of their eukaryotic hosts, and ultimately affect global nutrient cycles. Genome-resolved metagenomics is becoming an increasingly popular tool to assess the diversity and coding potential of giant viruses, but this approach is currently lacking validation.
Collapse
Affiliation(s)
| | - Julien Andreani
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Rania Francis
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Hadjer Boudjemaa
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille, France
- Department of Biology, Hassiba Ben Bouali University Chlef, Chlef, Algeria
| | | | - Janey Lee
- DOE Joint Genome Institute, Berkeley, California, USA
| | - Bernard La Scola
- Aix-Marseille Université, IRD, APHM, MEPHI, IHU Méditerranée Infection, Marseille, France
| | - Tanja Woyke
- DOE Joint Genome Institute, Berkeley, California, USA
| |
Collapse
|
39
|
The Puzzle of Coccoid Forms of Helicobacter pylori: Beyond Basic Science. Antibiotics (Basel) 2020; 9:antibiotics9060293. [PMID: 32486473 PMCID: PMC7345126 DOI: 10.3390/antibiotics9060293] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 05/19/2020] [Accepted: 05/29/2020] [Indexed: 01/06/2023] Open
Abstract
Helicobacter pylori (H. pylori) may enter a non-replicative, non-culturable, low metabolically active state, the so-called coccoid form, to survive in extreme environmental conditions. Since coccoid forms are not susceptible to antibiotics, they could represent a cause of therapy failure even in the absence of antibiotic resistance, i.e., relapse within one year. Furthermore, coccoid forms may colonize and infect the gastric mucosa in animal models and induce specific antibodies in animals and humans. Their detection is hard, since they are not culturable. Techniques, such as electron microscopy, polymerase chain reaction, loop-mediated isothermal amplification, flow cytometry and metagenomics, are promising even if current evidence is limited. Among the options for the treatment, some strategies have been suggested, such as a very high proton pump inhibitor dose, high-dose dual therapy, N-acetycysteine, linolenic acid and vonoprazan. These clinical, diagnostic and therapeutic uncertainties will represent fascinating challenges in the future.
Collapse
|
40
|
Salive AFV, Prudêncio CV, Baglinière F, Oliveira LL, Ferreira SO, Vanetti MCD. Comparison of stress conditions to induce viable but non-cultivable state in Salmonella. Braz J Microbiol 2020; 51:1269-1277. [PMID: 32291740 DOI: 10.1007/s42770-020-00261-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 03/10/2020] [Indexed: 12/18/2022] Open
Abstract
Salmonella can enter on the viable but non-culturable state (VBNC), characterized by the loss of ability to grow in routine culture media hindering detection by conventional methods and underestimation of the pathogen. Despite advances in research done so far, studies comparing conditions that lead Salmonella into the VBNC state are scarce. The main objective of this study was to evaluate different stresses to induce Salmonella to the VNBC state. Osmotic (1.2 M NaCl), acid (peracetic acid, 5.66 mg/mL) and oxidative (hydrogen peroxide, 1.20 mg/mL) stress were used at 4 °C to induce Salmonella enterica serovars Enteritidis and Typhimurium to the VBNC state. The culturability loss was monitored in the brain heart infusion (BHI) broth and agar, and the viability was determined by fluorescence microscopy, using the Live/Dead® kit, and by flow cytometry. Besides, the morphological characterization by atomic force microscopy (AFM) was performed. Storage in 1.2 M NaCl at 4 °C induced the VBNC state in Salmonella cells for periods longer than 121 days, and the percentage of viable cells has reached above 80.9%. More aggressive stress conditions promoted by peracetic acid and hydrogen peroxide induced the VBNC state in periods of, at most 0.14 day, and resulted in percentages of 8.5% to 45.5% viable cells, respectively. The counts of viable cells in the flow cytometer corroborate the results obtained by microscopic counts. The VBNC cells obtained in 1.2 M NaCl at 4 °C showed morphological changes, reducing the size and changing the morphology from bacillary to coccoid. No morphological change was observed on the cells stressed by acid or oxidant compounds.
Collapse
Affiliation(s)
| | - Cláudia Vieira Prudêncio
- Center of Biological and Health Sciences, Federal University of Western of Bahia, Barreiras, Bahia, Brazil
| | - François Baglinière
- Department of Microbiology, Federal University of Viçosa, Viçosa, Minas Gerais, Brazil
| | | | | | | |
Collapse
|
41
|
Han L, Wang K, Ma L, Delaquis P, Bach S, Feng J, Lu X. Viable but Nonculturable Escherichia coli O157:H7 and Salmonella enterica in Fresh Produce: Rapid Determination by Loop-Mediated Isothermal Amplification Coupled with a Propidium Monoazide Treatment. Appl Environ Microbiol 2020; 86:e02566-19. [PMID: 32005729 PMCID: PMC7082562 DOI: 10.1128/aem.02566-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Accepted: 01/21/2020] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli O157:H7 and Salmonella enterica are leading causes of foodborne outbreaks linked to fresh produce. Both species can enter the "viable but nonculturable" (VBNC) state that precludes detection using conventional culture-based or molecular methods. In this study, we assessed propidium monoazide-quantitative PCR (PMA-qPCR) assays and novel methods combining PMA and loop-mediated isothermal amplification (LAMP) for the detection and quantification of VBNC E. coli O157:H7 and S. enterica in fresh produce. The performance of PMA-LAMP assays targeting the wzy gene of E. coli O157:H7 and the agfA gene of S. enterica and the performance of PMA-qPCR assays were compared in pure culture and spiked tomato, lettuce, and spinach. No cross-reaction was observed in the specificity tests. The values representing the limit of detection (LOD) seen with PMA-LAMP were 9.0 CFU/reaction for E. coli O157:H7 and 4.6 CFU/reaction for S. enterica in pure culture and were 5.13 × 103 or 5.13 × 104 CFU/g for VBNC E. coli O157:H7 and 1.05 × 104 or 1.05 × 105 CFU/g for VBNC S. enterica in fresh produce, representing results comparable to those obtained by PMA-qPCR. Standard curves showed correlation coefficients ranging from 0.925 to 0.996, indicating a good quantitative capacity of PMA-LAMP for determining populations of both bacterial species in the VBNC state. The PMA-LAMP assay was completed with considerable economy of time (30 min versus 1 h) and achieved sensitivity and quantitative capacity comparable to those seen with a PMA-qPCR assay. PMA-LAMP is a rapid, sensitive, and robust method for the detection and quantification of VBNC E. coli O157:H7 and S. enterica in fresh produce.IMPORTANCE VBNC pathogenic bacteria pose a potential risk to the food industry because they do not multiply on routine microbiological media and thus can evade detection in conventional plating assays. Both E. coli O157:H7 and S. enterica have been reported to enter the VBNC state under a range of environmental stress conditions and to resuscitate under favorable conditions and are a potential cause of human infections. PMA-LAMP methods developed in this study provide a rapid, sensitive, and specific way to determine levels of VBNC E. coli O157:H7 and S. enterica in fresh produce, which potentially decreases the risks related to the consumption of fresh produce contaminated by enteric pathogens in this state. PMA-LAMP can be further applied in the field study to enhance our understanding of the fate of VBNC pathogens in the preharvest and postharvest stages of fresh produce.
Collapse
Affiliation(s)
- Lu Han
- Food, Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Kaidi Wang
- Food, Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Lina Ma
- Food, Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Pascal Delaquis
- Agriculture and Agri-Food Canada, Summerland Research and Development Centre, Summerland, British Columbia, Canada
| | - Susan Bach
- Agriculture and Agri-Food Canada, Summerland Research and Development Centre, Summerland, British Columbia, Canada
| | - Jinsong Feng
- Food, Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia, Canada
- Department of Microbiology and Immunology, The University of British Columbia, Vancouver, British Columbia, Canada
- Michael Smith Laboratories, The University of British Columbia, Vancouver, British Columbia, Canada
| | - Xiaonan Lu
- Food, Nutrition and Health Program, Faculty of Land and Food Systems, The University of British Columbia, Vancouver, British Columbia, Canada
| |
Collapse
|
42
|
RNA-based qPCR as a tool to quantify and to characterize dual-species biofilms. Sci Rep 2019; 9:13639. [PMID: 31541147 PMCID: PMC6754382 DOI: 10.1038/s41598-019-50094-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 09/06/2019] [Indexed: 12/22/2022] Open
Abstract
While considerable research has focused on studying individual-species, we now face the challenge of determining how interspecies interactions alter bacterial behaviours and pathogenesis. Pseudomonas aeruginosa and Staphylococcus aureus are often found to co-infect cystic-fibrosis patients. Curiously, their interaction is reported as competitive under laboratory conditions. Selecting appropriate methodologies is therefore critical to analyse multi-species communities. Herein, we demonstrated the major biases associated with qPCR quantification of bacterial populations and optimized a RNA-based qPCR able not only to quantify but also to characterize microbial interactions within dual-species biofilms composed by P. aeruginosa and S. aureus, as assessed by gene expression quantification. qPCR quantification was compared with flow-cytometry and culture-based quantification. Discrepancies between culture independent and culture dependent methods could be the result of the presence of viable but not-cultivable bacteria within the biofilm. Fluorescence microscopy confirmed this. A higher sensitivity to detect viable cells further highlights the potentialities of qPCR approach to quantify biofilm communities. By using bacterial RNA and an exogenous mRNA control, it was also possible to characterize bacterial transcriptomic profile, being this a major advantage of this method.
Collapse
|
43
|
Rubio E, Zboromyrska Y, Bosch J, Fernandez-Pittol MJ, Fidalgo BI, Fasanella A, Mons A, Román A, Casals-Pascual C, Vila J. Evaluation of flow cytometry for the detection of bacteria in biological fluids. PLoS One 2019; 14:e0220307. [PMID: 31390352 PMCID: PMC6685611 DOI: 10.1371/journal.pone.0220307] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Accepted: 07/12/2019] [Indexed: 01/18/2023] Open
Abstract
OBJECTIVES Conventional microbiological procedures for the isolation of bacteria from biological fluids consist of culture on solid media and enrichment broth. However, these methods can delay the microbiological identification for up to 4 days. The aim of this study was to evaluate the analytical performance of Sysmex UF500i (Sysmex, Kobe, Japan) as a screening method for the detection of bacteria in different biological fluids in comparison with direct Gram staining and the conventional culture on solid media and enrichment broth. METHODS A total of 479 biological fluid samples were included in the study (180 ascitic, 131 amniotic, 56 synovial, 40 cerebrospinal, 36 pleural, 24 peritoneal, 9 bile and 3 pericardial fluids). All samples were processed by conventional culture methods and analyzed by flow cytometry. Direct Gram staining was performed in 339 samples. The amount of growth on culture was recorded for positive samples. RESULTS Bacterial and white blood cell count by flow cytometry was significantly higher among culture positive samples and samples with a positive direct Gram stain compared to culture negative samples. Bacterial count directly correlated with the amount of growth on culture (Kruskall-Wallis H χ2(3) = 11.577, p = 0.009). The best specificity (95%) for bacterial count to predict culture positivity was achieved applying a cut-off value of 240 bacteria/μL. CONCLUSIONS Bacterial and white blood cell counts obtained with flow cytometry correlate with culture results in biological fluids. Bacterial count can be used as a complementary method along with the direct Gram stain to promptly detect positive samples and perform other diagnostic techniques in order to accelerate the bacterial detection and identification.
Collapse
Affiliation(s)
- Elisa Rubio
- Department of Microbiology, Biomedical Diagnostic Center (BDC), Hospital Clinic, University of Barcelona, Barcelona, Spain
- * E-mail:
| | - Yuliya Zboromyrska
- Consorci del Laboratori Intercomarcal de l´Alt Penedès, l´Anoia i el Garraf, Vilafranca del Penedès, Barcelona, Spain
| | - Jordi Bosch
- Department of Microbiology, Biomedical Diagnostic Center (BDC), Hospital Clinic, University of Barcelona, Barcelona, Spain
- ISGlobal, Barcelona, Institute for Global Health, Barcelona, Spain
| | - Mariana J. Fernandez-Pittol
- Department of Microbiology, Biomedical Diagnostic Center (BDC), Hospital Clinic, University of Barcelona, Barcelona, Spain
| | - Berta I. Fidalgo
- Department of Microbiology, Biomedical Diagnostic Center (BDC), Hospital Clinic, University of Barcelona, Barcelona, Spain
| | - Assumpta Fasanella
- Department of Microbiology, Biomedical Diagnostic Center (BDC), Hospital Clinic, University of Barcelona, Barcelona, Spain
| | - Anna Mons
- Department of Microbiology, Biomedical Diagnostic Center (BDC), Hospital Clinic, University of Barcelona, Barcelona, Spain
| | - Angely Román
- Department of Microbiology, Biomedical Diagnostic Center (BDC), Hospital Clinic, University of Barcelona, Barcelona, Spain
| | - Climent Casals-Pascual
- Department of Microbiology, Biomedical Diagnostic Center (BDC), Hospital Clinic, University of Barcelona, Barcelona, Spain
- ISGlobal, Barcelona, Institute for Global Health, Barcelona, Spain
| | - Jordi Vila
- Department of Microbiology, Biomedical Diagnostic Center (BDC), Hospital Clinic, University of Barcelona, Barcelona, Spain
- ISGlobal, Barcelona, Institute for Global Health, Barcelona, Spain
| |
Collapse
|
44
|
Conteduca D, Brunetti G, Dell'Olio F, Armenise MN, Krauss TF, Ciminelli C. Monitoring of individual bacteria using electro-photonic traps. BIOMEDICAL OPTICS EXPRESS 2019; 10:3463-3471. [PMID: 31467790 PMCID: PMC6706028 DOI: 10.1364/boe.10.003463] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/17/2019] [Accepted: 05/20/2019] [Indexed: 05/07/2023]
Abstract
Antimicrobial resistance (AMR) describes the ability of bacteria to become immune to antimicrobial treatments. Current testing for AMR is based on culturing methods that are very slow because they assess the average response of billions of bacteria. In principle, if tests were available that could assess the response of individual bacteria, they could be much faster. Here, we propose an electro-photonic approach for the analysis and the monitoring of susceptibility at the single-bacterium level. Our method employs optical tweezers based on photonic crystal cavities for the trapping of individual bacteria. While the bacteria are trapped, antibiotics can be added to the medium and the corresponding changes in the optical properties and motility of the bacteria be monitored via changes of the resonance wavelength and transmission. Furthermore, the proposed assay is able to monitor the impedance of the medium surrounding the bacterium, which allows us to record changes in metabolic rate in response to the antibiotic challenge. For example, our simulations predict a variation in measurable electrical current of up to 40% between dead and live bacteria. The proposed platform is the first, to our knowledge, that allows the parallel study of both the optical and the electrical response of individual bacteria to antibiotic challenge. Our platform opens up new lines of enquiry for monitoring the response of bacteria and it could lead the way towards the dissemination of a new generation of antibiogram study, which is relevant for the development of a point-of-care AMR diagnostics.
Collapse
Affiliation(s)
- Donato Conteduca
- Optoelectronics Laboratory, Politecnico di Bari, Via Orabona, 4, 70125, Bari, Italy
- Photonics Group, Department of Physics, University of York, Heslington, York, YO10 5DD, UK
| | - Giuseppe Brunetti
- Optoelectronics Laboratory, Politecnico di Bari, Via Orabona, 4, 70125, Bari, Italy
| | - Francesco Dell'Olio
- Optoelectronics Laboratory, Politecnico di Bari, Via Orabona, 4, 70125, Bari, Italy
| | - Mario N Armenise
- Optoelectronics Laboratory, Politecnico di Bari, Via Orabona, 4, 70125, Bari, Italy
| | - Thomas F Krauss
- Photonics Group, Department of Physics, University of York, Heslington, York, YO10 5DD, UK
| | - Caterina Ciminelli
- Optoelectronics Laboratory, Politecnico di Bari, Via Orabona, 4, 70125, Bari, Italy
| |
Collapse
|
45
|
Yu Y, Yin H, Peng H, Lu G, Dang Z. Biodegradation of decabromodiphenyl ether (BDE-209) using a novel microbial consortium GY1: Cells viability, pathway, toxicity assessment, and microbial function prediction. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 668:958-965. [PMID: 31018474 DOI: 10.1016/j.scitotenv.2019.03.078] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 03/04/2019] [Accepted: 03/06/2019] [Indexed: 06/09/2023]
Abstract
GY1, a novel microbial consortium with efficient ability to degrade decabromodiphenyl ether (BDE-209) has been isolated and the sequencing analysis has been conducted. The results revealed that Hyphomicrobium, Pseudomonas, Aminobacter, Sphingopyxis, Chryseobacterium, Bacillus, Pseudaminobacter, Stenotrophomonas, Sphingobacterium and Microbacterium were the dominant genera, and the function genes involved in BDE-209 conversion were predicted by PICRUSt. When BDE-209 concentration increased from 0.5 to 10mg/L, its degradation efficiency declined from 57.2% to 22.3%. Various kinds of debrominated metabolites were detected during the biodegradation process, including BDE-208, BDE-207, BDE-206, BDE-205, BDE-190, BDE-181, BDE-155, BDE-154, BDE-99, BDE-47, BDE-17 and BDE-7. Also, the proportion of necrotic cells was observed during GY1 mediated degradation of BDE-209 to reveal the changes of cells viability under BDE-209 stress. Subsequent analysis showed that the reaction of BDE-209 with GY1 was a detoxification process and bioaugmentation with GY1 effectively enhanced BDE-209 degradation in actual water and water-sediment system.
Collapse
Affiliation(s)
- Yuanyuan Yu
- Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangdong Provincial Engineering and Technology Research Center for Environmental Risk Prevention and Emergency Disposal, School of Environment and Energy, South China University of Technology, Guangzhou 510006, Guangdong, China
| | - Hua Yin
- Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangdong Provincial Engineering and Technology Research Center for Environmental Risk Prevention and Emergency Disposal, School of Environment and Energy, South China University of Technology, Guangzhou 510006, Guangdong, China.
| | - Hui Peng
- Department of Chemistry, Jinan University, Guangzhou 510632, Guangdong, China
| | - Guining Lu
- Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangdong Provincial Engineering and Technology Research Center for Environmental Risk Prevention and Emergency Disposal, School of Environment and Energy, South China University of Technology, Guangzhou 510006, Guangdong, China
| | - Zhi Dang
- Key Laboratory of Ministry of Education on Pollution Control and Ecosystem Restoration in Industry Clusters, Guangdong Provincial Engineering and Technology Research Center for Environmental Risk Prevention and Emergency Disposal, School of Environment and Energy, South China University of Technology, Guangzhou 510006, Guangdong, China
| |
Collapse
|
46
|
Sadasivam R, Sankarakuttalam C, Gopinath P. Hierarchical Architecture of Electrospun Hybrid PAN/Ag‐rGO/Fe3O4 Composite Nanofibrous Mat for Antibacterial Applications. ChemistrySelect 2019. [DOI: 10.1002/slct.201900007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Rajkumar Sadasivam
- Nanobiotechnology LaboratoryCentre for NanotechnologyIndian Institute of Technology Roorkee, Roorkee Uttarakhand- 247667 India
| | | | - Packirisamy Gopinath
- Nanobiotechnology LaboratoryCentre for NanotechnologyIndian Institute of Technology Roorkee, Roorkee Uttarakhand- 247667 India
- Department of BiotechnologyIndian Institute of Technology Roorkee, Roorkee Uttarakhand- 247667 India
| |
Collapse
|
47
|
Ou F, McGoverin C, Swift S, Vanholsbeeck F. Near real-time enumeration of live and dead bacteria using a fibre-based spectroscopic device. Sci Rep 2019; 9:4807. [PMID: 30886183 PMCID: PMC6423134 DOI: 10.1038/s41598-019-41221-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2018] [Accepted: 02/28/2019] [Indexed: 01/05/2023] Open
Abstract
A rapid, cost-effective and easy method that allows on-site determination of the concentration of live and dead bacterial cells using a fibre-based spectroscopic device (the optrode system) is proposed and demonstrated. Identification of live and dead bacteria was achieved by using the commercially available dyes SYTO 9 and propidium iodide, and fluorescence spectra were measured by the optrode. Three spectral processing methods were evaluated for their effectiveness in predicting the original bacterial concentration in the samples: principal components regression (PCR), partial least squares regression (PLSR) and support vector regression (SVR). Without any sample pre-concentration, PCR achieved the most reliable results. It was able to quantify live bacteria from 108 down to 106.2 bacteria/mL and showed the potential to detect as low as 105.7 bacteria/mL. Meanwhile, enumeration of dead bacteria using PCR was achieved between 108 and 107 bacteria/mL. The general procedures described in this article can be applied or modified for the enumeration of bacteria within populations stained with fluorescent dyes. The optrode is a promising device for the enumeration of live and dead bacterial populations particularly where rapid, on-site measurement and analysis is required.
Collapse
Affiliation(s)
- Fang Ou
- Department of Physics, The University of Auckland, Auckland, New Zealand.
- The Dodd-Walls Centre for Photonic and Quantum Technologies, Auckland, New Zealand.
| | - Cushla McGoverin
- Department of Physics, The University of Auckland, Auckland, New Zealand
- The Dodd-Walls Centre for Photonic and Quantum Technologies, Auckland, New Zealand
| | - Simon Swift
- School of Medical Sciences, The University of Auckland, Auckland, New Zealand
| | - Frédérique Vanholsbeeck
- Department of Physics, The University of Auckland, Auckland, New Zealand
- The Dodd-Walls Centre for Photonic and Quantum Technologies, Auckland, New Zealand
| |
Collapse
|
48
|
Safford HR, Bischel HN. Flow cytometry applications in water treatment, distribution, and reuse: A review. WATER RESEARCH 2019; 151:110-133. [PMID: 30594081 DOI: 10.1016/j.watres.2018.12.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 11/30/2018] [Accepted: 12/01/2018] [Indexed: 06/09/2023]
Abstract
Ensuring safe and effective water treatment, distribution, and reuse requires robust methods for characterizing and monitoring waterborne microbes. Methods widely used today can be limited by low sensitivity, high labor and time requirements, susceptibility to interference from inhibitory compounds, and difficulties in distinguishing between viable and non-viable cells. Flow cytometry (FCM) has recently gained attention as an alternative approach that can overcome many of these challenges. This article critically and systematically reviews for the first time recent literature on applications of FCM in water treatment, distribution, and reuse. In the review, we identify and examine nearly 300 studies published from 2000 to 2018 that illustrate the benefits and challenges of using FCM for assessing source-water quality and impacts of treatment-plant discharge on receiving waters, wastewater treatment, drinking water treatment, and drinking water distribution. We then discuss options for combining FCM with other indicators of water quality and address several topics that cut across nearly all applications reviewed. Finally, we identify priority areas in which more work is needed to realize the full potential of this approach. These include optimizing protocols for FCM-based analysis of waterborne viruses, optimizing protocols for specifically detecting target pathogens, automating sample handling and preparation to enable real-time FCM, developing computational tools to assist data analysis, and improving standards for instrumentation, methods, and reporting requirements. We conclude that while more work is needed to realize the full potential of FCM in water treatment, distribution, and reuse, substantial progress has been made over the past two decades. There is now a sufficiently large body of research documenting successful applications of FCM that the approach could reasonably and realistically see widespread adoption as a routine method for water quality assessment.
Collapse
Affiliation(s)
- Hannah R Safford
- Department of Civil and Environmental Engineering, University of California Davis, 2001 Ghausi Hall, 480 Bainer Hall Drive, 95616, Davis, CA, United States
| | - Heather N Bischel
- Department of Civil and Environmental Engineering, University of California Davis, 2001 Ghausi Hall, 480 Bainer Hall Drive, 95616, Davis, CA, United States.
| |
Collapse
|
49
|
Zhang G, Li B, Guo F, Liu J, Luan M, Liu Y, Guan Y. Taxonomic relatedness and environmental pressure synergistically drive the primary succession of biofilm microbial communities in reclaimed wastewater distribution systems. ENVIRONMENT INTERNATIONAL 2019; 124:25-37. [PMID: 30639905 DOI: 10.1016/j.envint.2018.12.040] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 12/17/2018] [Accepted: 12/17/2018] [Indexed: 06/09/2023]
Abstract
Compared to drinking water, the higher bacterial abundance, diversity, and organic matter concentration in reclaimed wastewater suggest that it is more likely to form biofilms. Nevertheless, little is known regarding many important aspects of the biofilm ecology in reclaimed wastewater distribution systems (RWDS), such as the long-term microbial community succession and the underlying driving factors. In the present study, by sampling and analysing microbial compositions of pipe wall biofilms from six frequently used pipe materials under NaClOdisinfection (sodium hypochlorite-treated), NONdisinfection (without disinfection), and UVdisinfection (UV-treated) treatments over one year, it was found that the succession of microbial community structure followed a primary succession pattern. This primary succession pattern was reflected as increases in live cell number and α-diversity, along with metagenic succession in taxonomic composition. Proteobacteria, Nitrospirae, Bacteroidetes, Acidobacteria, Planctomycetes, Actinobacteria, and Verrucomicrobia comprised the dominant phyla in biofilm samples. Compared to biofilms in the NaClOdisinfection reactor, the bacterial communities of biofilms in NONdisinfection and UVdisinfection reactors were distributed more evenly among different bacterial phyla. Principal component analysis revealed a clear temporal pattern of microbial community structures in six kinds of pipe wall biofilms albeit a difference in microbial community structures among the three reactors. Adonis testing indicated that the microbial community composition variation caused by disinfection methods (R2 = 0.283, P < 0.01) was more pronounced than that from the time variable (R2 = 0.070, P < 0.01) and pipe material (R2 = 0.057, P < 0.01). Significantly positive correlation between average local abundance and occupancy was observed in biofilm communities of the three reactors, suggesting that the 'core-satellite' model could be applied to identify biofilm-preferential species under specific disinfection conditions in RWDS. The prevalence of family Sphingomonadaceae, known to show chlorine tolerance and powerful biofilm-forming ability in NaClOdisinfection reactors, evidenced the habitat filtering consequent to environment pressure. Correlation-based network analysis revealed that taxonomic relatedness such as similar niches, cooperation, taxa overdispersion, and competition all functioned toward driving the bacterial assembly succession in RWDS.
Collapse
Affiliation(s)
- Guijuan Zhang
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen, China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control, School of Environment, Tsinghua University, Beijing, China
| | - Bing Li
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen, China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control, School of Environment, Tsinghua University, Beijing, China.
| | - Feng Guo
- School of Life Sciences, Xiamen University, Xiamen, China
| | - Jie Liu
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen, China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control, School of Environment, Tsinghua University, Beijing, China
| | - Mingqiang Luan
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen, China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control, School of Environment, Tsinghua University, Beijing, China
| | - Yang Liu
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen, China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control, School of Environment, Tsinghua University, Beijing, China
| | - Yuntao Guan
- Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen, China; State Environmental Protection Key Laboratory of Microorganism Application and Risk Control, School of Environment, Tsinghua University, Beijing, China.
| |
Collapse
|
50
|
A Combination of Linalool, Vitamin C, and Copper Synergistically Triggers Reactive Oxygen Species and DNA Damage and Inhibits Salmonella enterica subsp. enterica Serovar Typhi and Vibrio fluvialis. Appl Environ Microbiol 2019; 85:AEM.02487-18. [PMID: 30552187 DOI: 10.1128/aem.02487-18] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 11/26/2018] [Indexed: 11/20/2022] Open
Abstract
Inappropriate and disproportionate use of antibiotics is contributing immensely to the development of antibiotic resistance in bacterial species associated with food contamination. The use of natural products in combination can be a potent alternative hurdle strategy to inactivate foodborne pathogens. Here, we explored the pro-oxidant properties of essential oil linalool and vitamin C in combination with copper (LVC) in combating the foodborne pathogens Vibrio fluvialis and Salmonella enterica subsp. enterica serovar Typhi using a three-dimensional (3D) checkerboard microdilution assay. Antibacterial activity in terms of the MIC revealed that the triple combination exerted a synergistic effect compared to the effects of the individual constituents. The bactericidal effect of the triple combination was confirmed by a live/dead staining assay. Reactive oxygen species (ROS) measurements with the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling assay and scanning electron microscopy imaging strongly suggested that the increase in ROS production is the underlying mechanism of the enhanced antibacterial potency of the LVC combination (linalool [1.298 mM], vitamin C [8 mM], copper [16.3 μM]). In addition, the hypersensitivity of oxidative stress regulator mutants (oxyR, katG, ahpC, and sodA mutants) toward LVC corroborated the involvement of ROS in cell death. Live/dead staining and changes in cellular morphology revealed that oxidative stress did not transform the cells into the viable but nonculturable (VBNC) state; rather, killing was associated with intracellular and extracellular oxidative burst. Furthermore, the LVC combination did not display toxicity to human cells, while it effectively reduced the pathogen levels in acidic fruit juices by 3 to 4 log CFU/ml without adversely altering the organoleptic properties. This study opens a new outlook for combinatorial antimicrobial therapy.IMPORTANCE There is a need to develop effective antibacterial therapies for mitigating bacterial pathogens in food systems. We used a 3D checkerboard assay to ascertain a safe synergistic combination of food-grade components: vitamin C, copper, and the essential oil linalool. Individually, these constituents have to be added in large amounts to exert their antibacterial effect, which leads to unwanted organoleptic properties. The triple combination could exceptionally inhibit foodborne Gram-negative pathogens like Vibrio fluvialis and Salmonella enterica subsp. enterica serovar Typhi at low concentrations (linalool, 1.298 mM; vitamin C, 8 mM; copper, 16.3 μM) and displayed potent microbial inhibition in acidic beverages. We found increased susceptibility in deletion mutants of oxidative stress regulators (oxyR, katG, ahpC, and sodA mutants) due to ROS generation by Fenton's chemistry. The results of this study show that it may be possible to use plant-based antimicrobials in synergistic combinations to control microbial contaminants.
Collapse
|